diff --git a/BUILD b/BUILD
index 1ca357896a7da2154462c653e233be089c7c60df..503268383a8c5023df5ddae37cfd156b2da3eda6 100644
--- a/BUILD
+++ b/BUILD
@@ -285,6 +285,7 @@ cc_library(
     "src/core/ext/client_config/subchannel_call_holder.h",
     "src/core/ext/client_config/subchannel_index.h",
     "src/core/ext/client_config/uri_parser.h",
+    "third_party/objective_c/Cronet/cronet_c_for_grpc.h",
     "src/core/ext/lb_policy/grpclb/load_balancer_api.h",
     "src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h",
     "src/core/ext/census/aggregation.h",
@@ -439,6 +440,9 @@ cc_library(
     "src/core/ext/client_config/uri_parser.c",
     "src/core/ext/transport/chttp2/server/insecure/server_chttp2.c",
     "src/core/ext/transport/chttp2/client/insecure/channel_create.c",
+    "src/core/ext/transport/cronet/client/secure/cronet_channel_create.c",
+    "src/core/ext/transport/cronet/transport/cronet_api_dummy.c",
+    "src/core/ext/transport/cronet/transport/cronet_transport.c",
     "src/core/ext/lb_policy/grpclb/load_balancer_api.c",
     "src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c",
     "src/core/ext/lb_policy/pick_first/pick_first.c",
@@ -483,6 +487,7 @@ cc_library(
     "include/grpc/impl/codegen/sync_posix.h",
     "include/grpc/impl/codegen/sync_win32.h",
     "include/grpc/impl/codegen/time.h",
+    "include/grpc/grpc_cronet.h",
     "include/grpc/grpc_security.h",
     "include/grpc/grpc_security_constants.h",
     "include/grpc/census.h",
@@ -1464,6 +1469,9 @@ objc_library(
     "src/core/ext/client_config/uri_parser.c",
     "src/core/ext/transport/chttp2/server/insecure/server_chttp2.c",
     "src/core/ext/transport/chttp2/client/insecure/channel_create.c",
+    "src/core/ext/transport/cronet/client/secure/cronet_channel_create.c",
+    "src/core/ext/transport/cronet/transport/cronet_api_dummy.c",
+    "src/core/ext/transport/cronet/transport/cronet_transport.c",
     "src/core/ext/lb_policy/grpclb/load_balancer_api.c",
     "src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c",
     "src/core/ext/lb_policy/pick_first/pick_first.c",
@@ -1508,6 +1516,7 @@ objc_library(
     "include/grpc/impl/codegen/sync_posix.h",
     "include/grpc/impl/codegen/sync_win32.h",
     "include/grpc/impl/codegen/time.h",
+    "include/grpc/grpc_cronet.h",
     "include/grpc/grpc_security.h",
     "include/grpc/grpc_security_constants.h",
     "include/grpc/census.h",
@@ -1635,6 +1644,7 @@ objc_library(
     "src/core/ext/client_config/subchannel_call_holder.h",
     "src/core/ext/client_config/subchannel_index.h",
     "src/core/ext/client_config/uri_parser.h",
+    "third_party/objective_c/Cronet/cronet_c_for_grpc.h",
     "src/core/ext/lb_policy/grpclb/load_balancer_api.h",
     "src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h",
     "src/core/ext/census/aggregation.h",
diff --git a/Makefile b/Makefile
index f0a0ebd3eb6ca31471dbef1f4e614d735cc60df9..aa504dda20a27333919435f25a11ec83ecf2453d 100644
--- a/Makefile
+++ b/Makefile
@@ -2638,6 +2638,9 @@ LIBGRPC_SRC = \
     src/core/ext/client_config/uri_parser.c \
     src/core/ext/transport/chttp2/server/insecure/server_chttp2.c \
     src/core/ext/transport/chttp2/client/insecure/channel_create.c \
+    src/core/ext/transport/cronet/client/secure/cronet_channel_create.c \
+    src/core/ext/transport/cronet/transport/cronet_api_dummy.c \
+    src/core/ext/transport/cronet/transport/cronet_transport.c \
     src/core/ext/lb_policy/grpclb/load_balancer_api.c \
     src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c \
     third_party/nanopb/pb_common.c \
@@ -2685,6 +2688,7 @@ PUBLIC_HEADERS_C += \
     include/grpc/impl/codegen/sync_posix.h \
     include/grpc/impl/codegen/sync_win32.h \
     include/grpc/impl/codegen/time.h \
+    include/grpc/grpc_cronet.h \
     include/grpc/grpc_security.h \
     include/grpc/grpc_security_constants.h \
     include/grpc/census.h \
@@ -14399,6 +14403,9 @@ ifneq ($(OPENSSL_DEP),)
 # otherwise parallel compilation will fail if a source is compiled first.
 src/core/ext/transport/chttp2/client/secure/secure_channel_create.c: $(OPENSSL_DEP)
 src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c: $(OPENSSL_DEP)
+src/core/ext/transport/cronet/client/secure/cronet_channel_create.c: $(OPENSSL_DEP)
+src/core/ext/transport/cronet/transport/cronet_api_dummy.c: $(OPENSSL_DEP)
+src/core/ext/transport/cronet/transport/cronet_transport.c: $(OPENSSL_DEP)
 src/core/lib/http/httpcli_security_connector.c: $(OPENSSL_DEP)
 src/core/lib/security/b64.c: $(OPENSSL_DEP)
 src/core/lib/security/client_auth_filter.c: $(OPENSSL_DEP)
diff --git a/binding.gyp b/binding.gyp
index 8bc2aee3d1af1638d34eb5d61f6e1deae7efd30c..0d69fc58260d50960f6323163aef816b9f1f76fb 100644
--- a/binding.gyp
+++ b/binding.gyp
@@ -709,6 +709,9 @@
         'src/core/ext/client_config/uri_parser.c',
         'src/core/ext/transport/chttp2/server/insecure/server_chttp2.c',
         'src/core/ext/transport/chttp2/client/insecure/channel_create.c',
+        'src/core/ext/transport/cronet/client/secure/cronet_channel_create.c',
+        'src/core/ext/transport/cronet/transport/cronet_api_dummy.c',
+        'src/core/ext/transport/cronet/transport/cronet_transport.c',
         'src/core/ext/lb_policy/grpclb/load_balancer_api.c',
         'src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c',
         'third_party/nanopb/pb_common.c',
diff --git a/build.yaml b/build.yaml
index 187eb9ca8c6cd0d4e35cf118433f3b6928d92a4f..611b6398aae23202793690c4a31c32649fe79116 100644
--- a/build.yaml
+++ b/build.yaml
@@ -400,6 +400,7 @@ filegroups:
   - grpc_client_config
 - name: grpc_secure
   public_headers:
+  - include/grpc/grpc_cronet.h
   - include/grpc/grpc_security.h
   - include/grpc/grpc_security_constants.h
   headers:
@@ -547,6 +548,16 @@ filegroups:
   - grpc_transport_chttp2
   - grpc_base
   - grpc_secure
+- name: grpc_transport_cronet_client_secure
+  headers:
+  - third_party/objective_c/Cronet/cronet_c_for_grpc.h
+  src:
+  - src/core/ext/transport/cronet/client/secure/cronet_channel_create.c
+  - src/core/ext/transport/cronet/transport/cronet_api_dummy.c
+  - src/core/ext/transport/cronet/transport/cronet_transport.c
+  filegroups:
+  - grpc_base
+  - grpc_transport_chttp2
 - name: nanopb
   headers:
   - third_party/nanopb/pb.h
@@ -736,6 +747,7 @@ libs:
   - grpc_transport_chttp2_client_secure
   - grpc_transport_chttp2_server_insecure
   - grpc_transport_chttp2_client_insecure
+  - grpc_transport_cronet_client_secure
   - grpc_lb_policy_grpclb
   - grpc_lb_policy_pick_first
   - grpc_lb_policy_round_robin
diff --git a/config.m4 b/config.m4
index c8d2aae106cda1a77114d4da948b0b4432283e83..58c3d827361958cb9778b9e1357bb858f3c149eb 100644
--- a/config.m4
+++ b/config.m4
@@ -228,6 +228,9 @@ if test "$PHP_GRPC" != "no"; then
     src/core/ext/client_config/uri_parser.c \
     src/core/ext/transport/chttp2/server/insecure/server_chttp2.c \
     src/core/ext/transport/chttp2/client/insecure/channel_create.c \
+    src/core/ext/transport/cronet/client/secure/cronet_channel_create.c \
+    src/core/ext/transport/cronet/transport/cronet_api_dummy.c \
+    src/core/ext/transport/cronet/transport/cronet_transport.c \
     src/core/ext/lb_policy/grpclb/load_balancer_api.c \
     src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c \
     third_party/nanopb/pb_common.c \
@@ -566,6 +569,8 @@ if test "$PHP_GRPC" != "no"; then
   PHP_ADD_BUILD_DIR($ext_builddir/src/core/ext/transport/chttp2/server/insecure)
   PHP_ADD_BUILD_DIR($ext_builddir/src/core/ext/transport/chttp2/server/secure)
   PHP_ADD_BUILD_DIR($ext_builddir/src/core/ext/transport/chttp2/transport)
+  PHP_ADD_BUILD_DIR($ext_builddir/src/core/ext/transport/cronet/client/secure)
+  PHP_ADD_BUILD_DIR($ext_builddir/src/core/ext/transport/cronet/transport)
   PHP_ADD_BUILD_DIR($ext_builddir/src/core/lib/channel)
   PHP_ADD_BUILD_DIR($ext_builddir/src/core/lib/compression)
   PHP_ADD_BUILD_DIR($ext_builddir/src/core/lib/debug)
diff --git a/gRPC.podspec b/gRPC.podspec
index 393733209deef2d953c71fee9df9a5570d4fc13c..6b8f4779f7a015214f933b262d8a53af2cad407f 100644
--- a/gRPC.podspec
+++ b/gRPC.podspec
@@ -288,6 +288,7 @@ Pod::Spec.new do |s|
                       'src/core/ext/client_config/subchannel_call_holder.h',
                       'src/core/ext/client_config/subchannel_index.h',
                       'src/core/ext/client_config/uri_parser.h',
+                      'third_party/objective_c/Cronet/cronet_c_for_grpc.h',
                       'src/core/ext/lb_policy/grpclb/load_balancer_api.h',
                       'src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h',
                       'third_party/nanopb/pb.h',
@@ -326,6 +327,7 @@ Pod::Spec.new do |s|
                       'include/grpc/impl/codegen/sync_posix.h',
                       'include/grpc/impl/codegen/sync_win32.h',
                       'include/grpc/impl/codegen/time.h',
+                      'include/grpc/grpc_cronet.h',
                       'include/grpc/grpc_security.h',
                       'include/grpc/grpc_security_constants.h',
                       'include/grpc/census.h',
@@ -475,6 +477,9 @@ Pod::Spec.new do |s|
                       'src/core/ext/client_config/uri_parser.c',
                       'src/core/ext/transport/chttp2/server/insecure/server_chttp2.c',
                       'src/core/ext/transport/chttp2/client/insecure/channel_create.c',
+                      'src/core/ext/transport/cronet/client/secure/cronet_channel_create.c',
+                      'src/core/ext/transport/cronet/transport/cronet_api_dummy.c',
+                      'src/core/ext/transport/cronet/transport/cronet_transport.c',
                       'src/core/ext/lb_policy/grpclb/load_balancer_api.c',
                       'src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c',
                       'third_party/nanopb/pb_common.c',
@@ -631,6 +636,7 @@ Pod::Spec.new do |s|
                               'src/core/ext/client_config/subchannel_call_holder.h',
                               'src/core/ext/client_config/subchannel_index.h',
                               'src/core/ext/client_config/uri_parser.h',
+                              'third_party/objective_c/Cronet/cronet_c_for_grpc.h',
                               'src/core/ext/lb_policy/grpclb/load_balancer_api.h',
                               'src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h',
                               'third_party/nanopb/pb.h',
diff --git a/grpc.def b/grpc.def
index 61948ed1b8945fc2ea2fcd87e2fa47f9c8cc1a5d..09a94a6cd0c502fe2b053e40f38908504d35ab15 100644
--- a/grpc.def
+++ b/grpc.def
@@ -87,6 +87,7 @@ EXPORTS
     grpc_header_nonbin_value_is_legal
     grpc_is_binary_header
     grpc_call_error_to_string
+    grpc_cronet_secure_channel_create
     grpc_auth_property_iterator_next
     grpc_auth_context_property_iterator
     grpc_auth_context_peer_identity
diff --git a/grpc.gemspec b/grpc.gemspec
index 240ea1ca1ff5891399741bf788935df3d746f83d..d84f10a77f1d37ccd63b9637fe43b99c7ec972d5 100755
--- a/grpc.gemspec
+++ b/grpc.gemspec
@@ -169,6 +169,7 @@ Gem::Specification.new do |s|
   s.files += %w( include/grpc/impl/codegen/sync_posix.h )
   s.files += %w( include/grpc/impl/codegen/sync_win32.h )
   s.files += %w( include/grpc/impl/codegen/time.h )
+  s.files += %w( include/grpc/grpc_cronet.h )
   s.files += %w( include/grpc/grpc_security.h )
   s.files += %w( include/grpc/grpc_security_constants.h )
   s.files += %w( include/grpc/census.h )
@@ -296,6 +297,7 @@ Gem::Specification.new do |s|
   s.files += %w( src/core/ext/client_config/subchannel_call_holder.h )
   s.files += %w( src/core/ext/client_config/subchannel_index.h )
   s.files += %w( src/core/ext/client_config/uri_parser.h )
+  s.files += %w( third_party/objective_c/Cronet/cronet_c_for_grpc.h )
   s.files += %w( src/core/ext/lb_policy/grpclb/load_balancer_api.h )
   s.files += %w( src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h )
   s.files += %w( third_party/nanopb/pb.h )
@@ -454,6 +456,9 @@ Gem::Specification.new do |s|
   s.files += %w( src/core/ext/client_config/uri_parser.c )
   s.files += %w( src/core/ext/transport/chttp2/server/insecure/server_chttp2.c )
   s.files += %w( src/core/ext/transport/chttp2/client/insecure/channel_create.c )
+  s.files += %w( src/core/ext/transport/cronet/client/secure/cronet_channel_create.c )
+  s.files += %w( src/core/ext/transport/cronet/transport/cronet_api_dummy.c )
+  s.files += %w( src/core/ext/transport/cronet/transport/cronet_transport.c )
   s.files += %w( src/core/ext/lb_policy/grpclb/load_balancer_api.c )
   s.files += %w( src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c )
   s.files += %w( third_party/nanopb/pb_common.c )
diff --git a/include/grpc/grpc_cronet.h b/include/grpc/grpc_cronet.h
new file mode 100644
index 0000000000000000000000000000000000000000..295e0f55e80c4bec49fa86fe24769a0f20993fde
--- /dev/null
+++ b/include/grpc/grpc_cronet.h
@@ -0,0 +1,51 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef GRPC_GRPC_CRONET_H
+#define GRPC_GRPC_CRONET_H
+
+#include <grpc/grpc.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+GRPCAPI grpc_channel *grpc_cronet_secure_channel_create(
+    void *engine, const char *target, const grpc_channel_args *args,
+    void *reserved);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* GRPC_GRPC_CRONET_H */
diff --git a/package.xml b/package.xml
index 4c159e6024ca4450adf24fc1a754659747ea84be..cbdadb2d283b99028a9399a82f3b41fda6505a7c 100644
--- a/package.xml
+++ b/package.xml
@@ -176,6 +176,7 @@
     <file baseinstalldir="/" name="include/grpc/impl/codegen/sync_posix.h" role="src" />
     <file baseinstalldir="/" name="include/grpc/impl/codegen/sync_win32.h" role="src" />
     <file baseinstalldir="/" name="include/grpc/impl/codegen/time.h" role="src" />
+    <file baseinstalldir="/" name="include/grpc/grpc_cronet.h" role="src" />
     <file baseinstalldir="/" name="include/grpc/grpc_security.h" role="src" />
     <file baseinstalldir="/" name="include/grpc/grpc_security_constants.h" role="src" />
     <file baseinstalldir="/" name="include/grpc/census.h" role="src" />
@@ -303,6 +304,7 @@
     <file baseinstalldir="/" name="src/core/ext/client_config/subchannel_call_holder.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/client_config/subchannel_index.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/client_config/uri_parser.h" role="src" />
+    <file baseinstalldir="/" name="third_party/objective_c/Cronet/cronet_c_for_grpc.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/lb_policy/grpclb/load_balancer_api.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h" role="src" />
     <file baseinstalldir="/" name="third_party/nanopb/pb.h" role="src" />
@@ -461,6 +463,9 @@
     <file baseinstalldir="/" name="src/core/ext/client_config/uri_parser.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/transport/chttp2/server/insecure/server_chttp2.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/transport/chttp2/client/insecure/channel_create.c" role="src" />
+    <file baseinstalldir="/" name="src/core/ext/transport/cronet/client/secure/cronet_channel_create.c" role="src" />
+    <file baseinstalldir="/" name="src/core/ext/transport/cronet/transport/cronet_api_dummy.c" role="src" />
+    <file baseinstalldir="/" name="src/core/ext/transport/cronet/transport/cronet_transport.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/lb_policy/grpclb/load_balancer_api.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c" role="src" />
     <file baseinstalldir="/" name="third_party/nanopb/pb_common.c" role="src" />
diff --git a/src/core/ext/transport/cronet/client/secure/cronet_channel_create.c b/src/core/ext/transport/cronet/client/secure/cronet_channel_create.c
new file mode 100644
index 0000000000000000000000000000000000000000..df1acddcc08ae95a0f17de333f429e6cb5419aa5
--- /dev/null
+++ b/src/core/ext/transport/cronet/client/secure/cronet_channel_create.c
@@ -0,0 +1,69 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <grpc/impl/codegen/port_platform.h>
+
+#include <stdio.h>
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+
+#include "src/core/lib/surface/channel.h"
+#include "src/core/lib/transport/transport_impl.h"
+
+// Cronet transport object
+typedef struct cronet_transport {
+  grpc_transport base;  // must be first element in this structure
+  void *engine;
+  char *host;
+} cronet_transport;
+
+extern grpc_transport_vtable grpc_cronet_vtable;
+
+GRPCAPI grpc_channel *grpc_cronet_secure_channel_create(
+    void *engine, const char *target, const grpc_channel_args *args,
+    void *reserved) {
+  cronet_transport *ct = gpr_malloc(sizeof(cronet_transport));
+  ct->base.vtable = &grpc_cronet_vtable;
+  ct->engine = engine;
+  ct->host = gpr_malloc(strlen(target) + 1);
+  strcpy(ct->host, target);
+  gpr_log(GPR_DEBUG,
+          "grpc_create_cronet_transport: cronet_engine = %p, target=%s", engine,
+          ct->host);
+
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  return grpc_channel_create(&exec_ctx, target, args,
+                             GRPC_CLIENT_DIRECT_CHANNEL, (grpc_transport *)ct);
+}
diff --git a/src/core/ext/transport/cronet/transport/cronet_api_dummy.c b/src/core/ext/transport/cronet/transport/cronet_api_dummy.c
new file mode 100644
index 0000000000000000000000000000000000000000..687026c9fde99af4d164103a2bf90c56e7e10ceb
--- /dev/null
+++ b/src/core/ext/transport/cronet/transport/cronet_api_dummy.c
@@ -0,0 +1,85 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+/* This file has empty implementation of all the functions exposed by the cronet
+library, so we can build it in all environments */
+
+#include <stdbool.h>
+
+#include <grpc/support/log.h>
+
+#include "third_party/objective_c/Cronet/cronet_c_for_grpc.h"
+
+#ifdef GRPC_COMPILE_WITH_CRONET
+/* link with the real CRONET library in the build system */
+#else
+/* Dummy implementation of cronet API just to test for build-ability */
+cronet_bidirectional_stream* cronet_bidirectional_stream_create(
+    cronet_engine* engine, void* annotation,
+    cronet_bidirectional_stream_callback* callback) {
+  GPR_ASSERT(0);
+  return NULL;
+}
+
+int cronet_bidirectional_stream_destroy(cronet_bidirectional_stream* stream) {
+  GPR_ASSERT(0);
+  return 0;
+}
+
+int cronet_bidirectional_stream_start(
+    cronet_bidirectional_stream* stream, const char* url, int priority,
+    const char* method, const cronet_bidirectional_stream_header_array* headers,
+    bool end_of_stream) {
+  GPR_ASSERT(0);
+  return 0;
+}
+
+int cronet_bidirectional_stream_read(cronet_bidirectional_stream* stream,
+                                     char* buffer, int capacity) {
+  GPR_ASSERT(0);
+  return 0;
+}
+
+int cronet_bidirectional_stream_write(cronet_bidirectional_stream* stream,
+                                      const char* buffer, int count,
+                                      bool end_of_stream) {
+  GPR_ASSERT(0);
+  return 0;
+}
+
+int cronet_bidirectional_stream_cancel(cronet_bidirectional_stream* stream) {
+  GPR_ASSERT(0);
+  return 0;
+}
+
+#endif /* GRPC_COMPILE_WITH_CRONET */
diff --git a/src/core/ext/transport/cronet/transport/cronet_transport.c b/src/core/ext/transport/cronet/transport/cronet_transport.c
new file mode 100644
index 0000000000000000000000000000000000000000..5bb085195c6abd76e18d9fdf6afd712d78bc321e
--- /dev/null
+++ b/src/core/ext/transport/cronet/transport/cronet_transport.c
@@ -0,0 +1,640 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <string.h>
+
+#include <grpc/impl/codegen/port_platform.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/host_port.h>
+#include <grpc/support/log.h>
+#include <grpc/support/slice_buffer.h>
+#include <grpc/support/string_util.h>
+#include <grpc/support/useful.h>
+
+#include "src/core/ext/transport/chttp2/transport/incoming_metadata.h"
+#include "src/core/lib/iomgr/exec_ctx.h"
+#include "src/core/lib/support/string.h"
+#include "src/core/lib/surface/channel.h"
+#include "src/core/lib/transport/metadata_batch.h"
+#include "src/core/lib/transport/transport_impl.h"
+#include "third_party/objective_c/Cronet/cronet_c_for_grpc.h"
+
+#define GRPC_HEADER_SIZE_IN_BYTES 5
+
+// Global flag that gets set with GRPC_TRACE env variable
+int grpc_cronet_trace = 1;
+
+// Cronet transport object
+struct grpc_cronet_transport {
+  grpc_transport base; /* must be first element in this structure */
+  cronet_engine *engine;
+  char *host;
+};
+
+typedef struct grpc_cronet_transport grpc_cronet_transport;
+
+enum send_state {
+  CRONET_SEND_IDLE = 0,
+  CRONET_REQ_STARTED,
+  CRONET_SEND_HEADER,
+  CRONET_WRITE,
+  CRONET_WRITE_COMPLETED,
+};
+
+enum recv_state {
+  CRONET_RECV_IDLE = 0,
+  CRONET_RECV_READ_LENGTH,
+  CRONET_RECV_READ_DATA,
+  CRONET_RECV_CLOSED,
+};
+
+static const char *recv_state_name[] = {
+    "CRONET_RECV_IDLE", "CRONET_RECV_READ_LENGTH", "CRONET_RECV_READ_DATA,",
+    "CRONET_RECV_CLOSED"};
+
+// Enum that identifies calling function.
+enum e_caller {
+  PERFORM_STREAM_OP,
+  ON_READ_COMPLETE,
+  ON_RESPONSE_HEADERS_RECEIVED,
+  ON_RESPONSE_TRAILERS_RECEIVED
+};
+
+enum callback_id {
+  CB_SEND_INITIAL_METADATA = 0,
+  CB_SEND_MESSAGE,
+  CB_SEND_TRAILING_METADATA,
+  CB_RECV_MESSAGE,
+  CB_RECV_INITIAL_METADATA,
+  CB_RECV_TRAILING_METADATA,
+  CB_NUM_CALLBACKS
+};
+
+struct stream_obj {
+  // we store received bytes here as they trickle in.
+  gpr_slice_buffer write_slice_buffer;
+  cronet_bidirectional_stream *cbs;
+  gpr_slice slice;
+  gpr_slice_buffer read_slice_buffer;
+  struct grpc_slice_buffer_stream sbs;
+  char *read_buffer;
+  int remaining_read_bytes;
+  int total_read_bytes;
+
+  char *write_buffer;
+  size_t write_buffer_size;
+
+  // Hold the URL
+  char *url;
+
+  bool response_headers_received;
+  bool read_requested;
+  bool response_trailers_received;
+  bool read_closed;
+
+  // Recv message stuff
+  grpc_byte_buffer **recv_message;
+  // Initial metadata stuff
+  grpc_metadata_batch *recv_initial_metadata;
+  // Trailing metadata stuff
+  grpc_metadata_batch *recv_trailing_metadata;
+  grpc_chttp2_incoming_metadata_buffer imb;
+
+  // This mutex protects receive state machine execution
+  gpr_mu recv_mu;
+  // we can queue up up to 2 callbacks for each OP
+  grpc_closure *callback_list[CB_NUM_CALLBACKS][2];
+
+  // storage for header
+  cronet_bidirectional_stream_header *headers;
+  uint32_t num_headers;
+  cronet_bidirectional_stream_header_array header_array;
+  // state tracking
+  enum recv_state cronet_recv_state;
+  enum send_state cronet_send_state;
+};
+
+typedef struct stream_obj stream_obj;
+
+static void next_send_step(stream_obj *s);
+static void next_recv_step(stream_obj *s, enum e_caller caller);
+
+static void set_pollset_do_nothing(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
+                                   grpc_stream *gs, grpc_pollset *pollset) {}
+
+static void enqueue_callbacks(grpc_closure *callback_list[]) {
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  if (callback_list[0]) {
+    grpc_exec_ctx_enqueue(&exec_ctx, callback_list[0], true, NULL);
+    callback_list[0] = NULL;
+  }
+  if (callback_list[1]) {
+    grpc_exec_ctx_enqueue(&exec_ctx, callback_list[1], true, NULL);
+    callback_list[1] = NULL;
+  }
+  grpc_exec_ctx_finish(&exec_ctx);
+}
+
+static void on_canceled(cronet_bidirectional_stream *stream) {
+  if (grpc_cronet_trace) {
+    gpr_log(GPR_DEBUG, "on_canceled %p", stream);
+  }
+}
+
+static void on_failed(cronet_bidirectional_stream *stream, int net_error) {
+  if (grpc_cronet_trace) {
+    gpr_log(GPR_DEBUG, "on_failed %p, error = %d", stream, net_error);
+  }
+}
+
+static void on_succeeded(cronet_bidirectional_stream *stream) {
+  if (grpc_cronet_trace) {
+    gpr_log(GPR_DEBUG, "on_succeeded %p", stream);
+  }
+}
+
+static void on_response_trailers_received(
+    cronet_bidirectional_stream *stream,
+    const cronet_bidirectional_stream_header_array *trailers) {
+  if (grpc_cronet_trace) {
+    gpr_log(GPR_DEBUG, "R: on_response_trailers_received");
+  }
+  stream_obj *s = (stream_obj *)stream->annotation;
+
+  memset(&s->imb, 0, sizeof(s->imb));
+  grpc_chttp2_incoming_metadata_buffer_init(&s->imb);
+  unsigned int i = 0;
+  for (i = 0; i < trailers->count; i++) {
+    grpc_chttp2_incoming_metadata_buffer_add(
+        &s->imb, grpc_mdelem_from_metadata_strings(
+                     grpc_mdstr_from_string(trailers->headers[i].key),
+                     grpc_mdstr_from_string(trailers->headers[i].value)));
+  }
+  s->response_trailers_received = true;
+  next_recv_step(s, ON_RESPONSE_TRAILERS_RECEIVED);
+}
+
+static void on_write_completed(cronet_bidirectional_stream *stream,
+                               const char *data) {
+  if (grpc_cronet_trace) {
+    gpr_log(GPR_DEBUG, "W: on_write_completed");
+  }
+  stream_obj *s = (stream_obj *)stream->annotation;
+  enqueue_callbacks(s->callback_list[CB_SEND_MESSAGE]);
+  s->cronet_send_state = CRONET_WRITE_COMPLETED;
+  next_send_step(s);
+}
+
+static void process_recv_message(stream_obj *s, const uint8_t *recv_data) {
+  gpr_slice read_data_slice = gpr_slice_malloc((uint32_t)s->total_read_bytes);
+  uint8_t *dst_p = GPR_SLICE_START_PTR(read_data_slice);
+  memcpy(dst_p, recv_data, (size_t)s->total_read_bytes);
+  gpr_slice_buffer_add(&s->read_slice_buffer, read_data_slice);
+  grpc_slice_buffer_stream_init(&s->sbs, &s->read_slice_buffer, 0);
+  *s->recv_message = (grpc_byte_buffer *)&s->sbs;
+}
+
+static int parse_grpc_header(const uint8_t *data) {
+  const uint8_t *p = data + 1;
+  int length = 0;
+  length |= ((uint8_t)*p++) << 24;
+  length |= ((uint8_t)*p++) << 16;
+  length |= ((uint8_t)*p++) << 8;
+  length |= ((uint8_t)*p++);
+  return length;
+}
+
+static void on_read_completed(cronet_bidirectional_stream *stream, char *data,
+                              int count) {
+  stream_obj *s = (stream_obj *)stream->annotation;
+  if (grpc_cronet_trace) {
+    gpr_log(GPR_DEBUG, "R: on_read_completed count=%d, total=%d, remaining=%d",
+            count, s->total_read_bytes, s->remaining_read_bytes);
+  }
+  if (count > 0) {
+    GPR_ASSERT(s->recv_message);
+    s->remaining_read_bytes -= count;
+    next_recv_step(s, ON_READ_COMPLETE);
+  } else {
+    s->read_closed = true;
+    next_recv_step(s, ON_READ_COMPLETE);
+  }
+}
+
+static void on_response_headers_received(
+    cronet_bidirectional_stream *stream,
+    const cronet_bidirectional_stream_header_array *headers,
+    const char *negotiated_protocol) {
+  if (grpc_cronet_trace) {
+    gpr_log(GPR_DEBUG, "R: on_response_headers_received");
+  }
+  stream_obj *s = (stream_obj *)stream->annotation;
+  enqueue_callbacks(s->callback_list[CB_RECV_INITIAL_METADATA]);
+  s->response_headers_received = true;
+  next_recv_step(s, ON_RESPONSE_HEADERS_RECEIVED);
+}
+
+static void on_request_headers_sent(cronet_bidirectional_stream *stream) {
+  if (grpc_cronet_trace) {
+    gpr_log(GPR_DEBUG, "W: on_request_headers_sent");
+  }
+  stream_obj *s = (stream_obj *)stream->annotation;
+  enqueue_callbacks(s->callback_list[CB_SEND_INITIAL_METADATA]);
+  s->cronet_send_state = CRONET_SEND_HEADER;
+  next_send_step(s);
+}
+
+// Callback function pointers (invoked by cronet in response to events)
+static cronet_bidirectional_stream_callback callbacks = {
+    on_request_headers_sent,
+    on_response_headers_received,
+    on_read_completed,
+    on_write_completed,
+    on_response_trailers_received,
+    on_succeeded,
+    on_failed,
+    on_canceled};
+
+static void invoke_closing_callback(stream_obj *s) {
+  grpc_chttp2_incoming_metadata_buffer_publish(&s->imb,
+                                               s->recv_trailing_metadata);
+  if (s->callback_list[CB_RECV_TRAILING_METADATA]) {
+    enqueue_callbacks(s->callback_list[CB_RECV_TRAILING_METADATA]);
+  }
+}
+
+static void set_recv_state(stream_obj *s, enum recv_state state) {
+  if (grpc_cronet_trace) {
+    gpr_log(GPR_DEBUG, "next_state = %s", recv_state_name[state]);
+  }
+  s->cronet_recv_state = state;
+}
+
+// This is invoked from perform_stream_op, and all on_xxxx callbacks.
+static void next_recv_step(stream_obj *s, enum e_caller caller) {
+  gpr_mu_lock(&s->recv_mu);
+  switch (s->cronet_recv_state) {
+    case CRONET_RECV_IDLE:
+      if (grpc_cronet_trace) {
+        gpr_log(GPR_DEBUG, "cronet_recv_state = CRONET_RECV_IDLE");
+      }
+      if (caller == PERFORM_STREAM_OP ||
+          caller == ON_RESPONSE_HEADERS_RECEIVED) {
+        if (s->read_closed && s->response_trailers_received) {
+          invoke_closing_callback(s);
+          set_recv_state(s, CRONET_RECV_CLOSED);
+        } else if (s->response_headers_received == true &&
+                   s->read_requested == true) {
+          set_recv_state(s, CRONET_RECV_READ_LENGTH);
+          s->total_read_bytes = s->remaining_read_bytes =
+              GRPC_HEADER_SIZE_IN_BYTES;
+          GPR_ASSERT(s->read_buffer);
+          if (grpc_cronet_trace) {
+            gpr_log(GPR_DEBUG, "R: cronet_bidirectional_stream_read()");
+          }
+          cronet_bidirectional_stream_read(s->cbs, s->read_buffer,
+                                           s->remaining_read_bytes);
+        }
+      }
+      break;
+    case CRONET_RECV_READ_LENGTH:
+      if (grpc_cronet_trace) {
+        gpr_log(GPR_DEBUG, "cronet_recv_state = CRONET_RECV_READ_LENGTH");
+      }
+      if (caller == ON_READ_COMPLETE) {
+        if (s->read_closed) {
+          invoke_closing_callback(s);
+          enqueue_callbacks(s->callback_list[CB_RECV_MESSAGE]);
+          set_recv_state(s, CRONET_RECV_CLOSED);
+        } else {
+          GPR_ASSERT(s->remaining_read_bytes == 0);
+          set_recv_state(s, CRONET_RECV_READ_DATA);
+          s->total_read_bytes = s->remaining_read_bytes =
+              parse_grpc_header((const uint8_t *)s->read_buffer);
+          s->read_buffer =
+              gpr_realloc(s->read_buffer, (uint32_t)s->remaining_read_bytes);
+          GPR_ASSERT(s->read_buffer);
+          if (grpc_cronet_trace) {
+            gpr_log(GPR_DEBUG, "R: cronet_bidirectional_stream_read()");
+          }
+          cronet_bidirectional_stream_read(s->cbs, (char *)s->read_buffer,
+                                           s->remaining_read_bytes);
+        }
+      }
+      break;
+    case CRONET_RECV_READ_DATA:
+      if (grpc_cronet_trace) {
+        gpr_log(GPR_DEBUG, "cronet_recv_state = CRONET_RECV_READ_DATA");
+      }
+      if (caller == ON_READ_COMPLETE) {
+        if (s->remaining_read_bytes > 0) {
+          int offset = s->total_read_bytes - s->remaining_read_bytes;
+          GPR_ASSERT(s->read_buffer);
+          if (grpc_cronet_trace) {
+            gpr_log(GPR_DEBUG, "R: cronet_bidirectional_stream_read()");
+          }
+          cronet_bidirectional_stream_read(
+              s->cbs, (char *)s->read_buffer + offset, s->remaining_read_bytes);
+        } else {
+          gpr_slice_buffer_init(&s->read_slice_buffer);
+          uint8_t *p = (uint8_t *)s->read_buffer;
+          process_recv_message(s, p);
+          set_recv_state(s, CRONET_RECV_IDLE);
+          enqueue_callbacks(s->callback_list[CB_RECV_MESSAGE]);
+        }
+      }
+      break;
+    case CRONET_RECV_CLOSED:
+      break;
+    default:
+      GPR_ASSERT(0);  // Should not reach here
+      break;
+  }
+  gpr_mu_unlock(&s->recv_mu);
+}
+
+// This function takes the data from s->write_slice_buffer and assembles into
+// a contiguous byte stream with 5 byte gRPC header prepended.
+static void create_grpc_frame(stream_obj *s) {
+  gpr_slice slice = gpr_slice_buffer_take_first(&s->write_slice_buffer);
+  uint8_t *raw_data = GPR_SLICE_START_PTR(slice);
+  size_t length = GPR_SLICE_LENGTH(slice);
+  s->write_buffer_size = length + GRPC_HEADER_SIZE_IN_BYTES;
+  s->write_buffer = gpr_realloc(s->write_buffer, s->write_buffer_size);
+  uint8_t *p = (uint8_t *)s->write_buffer;
+  // Append 5 byte header
+  *p++ = 0;
+  *p++ = (uint8_t)(length >> 24);
+  *p++ = (uint8_t)(length >> 16);
+  *p++ = (uint8_t)(length >> 8);
+  *p++ = (uint8_t)(length);
+  // append actual data
+  memcpy(p, raw_data, length);
+}
+
+static void do_write(stream_obj *s) {
+  gpr_slice_buffer *sb = &s->write_slice_buffer;
+  GPR_ASSERT(sb->count <= 1);
+  if (sb->count > 0) {
+    create_grpc_frame(s);
+    if (grpc_cronet_trace) {
+      gpr_log(GPR_DEBUG, "W: cronet_bidirectional_stream_write");
+    }
+    cronet_bidirectional_stream_write(s->cbs, s->write_buffer,
+                                      (int)s->write_buffer_size, false);
+  }
+}
+
+//
+static void next_send_step(stream_obj *s) {
+  switch (s->cronet_send_state) {
+    case CRONET_SEND_IDLE:
+      GPR_ASSERT(
+          s->cbs);  // cronet_bidirectional_stream is not initialized yet.
+      s->cronet_send_state = CRONET_REQ_STARTED;
+      if (grpc_cronet_trace) {
+        gpr_log(GPR_DEBUG, "cronet_bidirectional_stream_start to %s", s->url);
+      }
+      cronet_bidirectional_stream_start(s->cbs, s->url, 0, "POST",
+                                        &s->header_array, false);
+      // we no longer need the memory that was allocated earlier.
+      gpr_free(s->header_array.headers);
+      break;
+    case CRONET_SEND_HEADER:
+      do_write(s);
+      s->cronet_send_state = CRONET_WRITE;
+      break;
+    case CRONET_WRITE_COMPLETED:
+      do_write(s);
+      break;
+    default:
+      GPR_ASSERT(0);
+      break;
+  }
+}
+
+static void convert_metadata_to_cronet_headers(grpc_linked_mdelem *head,
+                                               const char *host,
+                                               stream_obj *s) {
+  grpc_linked_mdelem *curr = head;
+  // Walk the linked list and get number of header fields
+  uint32_t num_headers_available = 0;
+  while (curr != NULL) {
+    curr = curr->next;
+    num_headers_available++;
+  }
+  // Allocate enough memory
+  s->headers = (cronet_bidirectional_stream_header *)gpr_malloc(
+      sizeof(cronet_bidirectional_stream_header) * num_headers_available);
+
+  // Walk the linked list again, this time copying the header fields.
+  // s->num_headers
+  // can be less than num_headers_available, as some headers are not used for
+  // cronet
+  curr = head;
+  s->num_headers = 0;
+  while (s->num_headers < num_headers_available) {
+    grpc_mdelem *mdelem = curr->md;
+    curr = curr->next;
+    const char *key = grpc_mdstr_as_c_string(mdelem->key);
+    const char *value = grpc_mdstr_as_c_string(mdelem->value);
+    if (strcmp(key, ":scheme") == 0 || strcmp(key, ":method") == 0 ||
+        strcmp(key, ":authority") == 0) {
+      // Cronet populates these fields on its own.
+      continue;
+    }
+    if (strcmp(key, ":path") == 0) {
+      // Create URL by appending :path value to the hostname
+      gpr_asprintf(&s->url, "https://%s%s", host, value);
+      if (grpc_cronet_trace) {
+        gpr_log(GPR_DEBUG, "extracted URL = %s", s->url);
+      }
+      continue;
+    }
+    s->headers[s->num_headers].key = key;
+    s->headers[s->num_headers].value = value;
+    s->num_headers++;
+    if (curr == NULL) {
+      break;
+    }
+  }
+}
+
+static void perform_stream_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
+                              grpc_stream *gs, grpc_transport_stream_op *op) {
+  grpc_cronet_transport *ct = (grpc_cronet_transport *)gt;
+  GPR_ASSERT(ct->engine);
+  stream_obj *s = (stream_obj *)gs;
+  if (op->recv_trailing_metadata) {
+    if (grpc_cronet_trace) {
+      gpr_log(GPR_DEBUG,
+              "perform_stream_op - recv_trailing_metadata: on_complete=%p",
+              op->on_complete);
+    }
+    s->recv_trailing_metadata = op->recv_trailing_metadata;
+    GPR_ASSERT(!s->callback_list[CB_RECV_TRAILING_METADATA][0]);
+    s->callback_list[CB_RECV_TRAILING_METADATA][0] = op->on_complete;
+  }
+  if (op->recv_message) {
+    if (grpc_cronet_trace) {
+      gpr_log(GPR_DEBUG, "perform_stream_op - recv_message: on_complete=%p",
+              op->on_complete);
+    }
+    s->recv_message = (grpc_byte_buffer **)op->recv_message;
+    GPR_ASSERT(!s->callback_list[CB_RECV_MESSAGE][0]);
+    GPR_ASSERT(!s->callback_list[CB_RECV_MESSAGE][1]);
+    s->callback_list[CB_RECV_MESSAGE][0] = op->recv_message_ready;
+    s->callback_list[CB_RECV_MESSAGE][1] = op->on_complete;
+    s->read_requested = true;
+    next_recv_step(s, PERFORM_STREAM_OP);
+  }
+  if (op->recv_initial_metadata) {
+    if (grpc_cronet_trace) {
+      gpr_log(GPR_DEBUG, "perform_stream_op - recv_initial_metadata:=%p",
+              op->on_complete);
+    }
+    s->recv_initial_metadata = op->recv_initial_metadata;
+    GPR_ASSERT(!s->callback_list[CB_RECV_INITIAL_METADATA][0]);
+    GPR_ASSERT(!s->callback_list[CB_RECV_INITIAL_METADATA][1]);
+    s->callback_list[CB_RECV_INITIAL_METADATA][0] =
+        op->recv_initial_metadata_ready;
+    s->callback_list[CB_RECV_INITIAL_METADATA][1] = op->on_complete;
+  }
+  if (op->send_initial_metadata) {
+    if (grpc_cronet_trace) {
+      gpr_log(GPR_DEBUG,
+              "perform_stream_op - send_initial_metadata: on_complete=%p",
+              op->on_complete);
+    }
+    s->num_headers = 0;
+    convert_metadata_to_cronet_headers(op->send_initial_metadata->list.head,
+                                       ct->host, s);
+    s->header_array.count = s->num_headers;
+    s->header_array.capacity = s->num_headers;
+    s->header_array.headers = s->headers;
+    GPR_ASSERT(!s->callback_list[CB_SEND_INITIAL_METADATA][0]);
+    s->callback_list[CB_SEND_INITIAL_METADATA][0] = op->on_complete;
+  }
+  if (op->send_message) {
+    if (grpc_cronet_trace) {
+      gpr_log(GPR_DEBUG, "perform_stream_op - send_message: on_complete=%p",
+              op->on_complete);
+    }
+    grpc_byte_stream_next(exec_ctx, op->send_message, &s->slice,
+                          op->send_message->length, NULL);
+    // Check that compression flag is not ON. We don't support compression yet.
+    // TODO (makdharma): add compression support
+    GPR_ASSERT(op->send_message->flags == 0);
+    gpr_slice_buffer_add(&s->write_slice_buffer, s->slice);
+    if (s->cbs == NULL) {
+      if (grpc_cronet_trace) {
+        gpr_log(GPR_DEBUG, "cronet_bidirectional_stream_create");
+      }
+      s->cbs = cronet_bidirectional_stream_create(ct->engine, s, &callbacks);
+      GPR_ASSERT(s->cbs);
+      s->read_closed = false;
+      s->response_trailers_received = false;
+      s->response_headers_received = false;
+      s->cronet_send_state = CRONET_SEND_IDLE;
+      s->cronet_recv_state = CRONET_RECV_IDLE;
+    }
+    GPR_ASSERT(!s->callback_list[CB_SEND_MESSAGE][0]);
+    s->callback_list[CB_SEND_MESSAGE][0] = op->on_complete;
+    next_send_step(s);
+  }
+  if (op->send_trailing_metadata) {
+    if (grpc_cronet_trace) {
+      gpr_log(GPR_DEBUG,
+              "perform_stream_op - send_trailing_metadata: on_complete=%p",
+              op->on_complete);
+    }
+    GPR_ASSERT(!s->callback_list[CB_SEND_TRAILING_METADATA][0]);
+    s->callback_list[CB_SEND_TRAILING_METADATA][0] = op->on_complete;
+    if (s->cbs) {
+      // Send an "empty" write to the far end to signal that we're done.
+      // This will induce the server to send down trailers.
+      if (grpc_cronet_trace) {
+        gpr_log(GPR_DEBUG, "W: cronet_bidirectional_stream_write");
+      }
+      cronet_bidirectional_stream_write(s->cbs, "abc", 0, true);
+    } else {
+      // We never created a stream. This was probably an empty request.
+      invoke_closing_callback(s);
+    }
+  }
+}
+
+static int init_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
+                       grpc_stream *gs, grpc_stream_refcount *refcount,
+                       const void *server_data) {
+  stream_obj *s = (stream_obj *)gs;
+  memset(s->callback_list, 0, sizeof(s->callback_list));
+  s->cbs = NULL;
+  gpr_mu_init(&s->recv_mu);
+  s->read_buffer = gpr_malloc(GRPC_HEADER_SIZE_IN_BYTES);
+  s->write_buffer = gpr_malloc(GRPC_HEADER_SIZE_IN_BYTES);
+  gpr_slice_buffer_init(&s->write_slice_buffer);
+  if (grpc_cronet_trace) {
+    gpr_log(GPR_DEBUG, "cronet_transport - init_stream");
+  }
+  return 0;
+}
+
+static void destroy_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
+                           grpc_stream *gs, void *and_free_memory) {
+  if (grpc_cronet_trace) {
+    gpr_log(GPR_DEBUG, "Destroy stream");
+  }
+  stream_obj *s = (stream_obj *)gs;
+  s->cbs = NULL;
+  gpr_free(s->read_buffer);
+  gpr_free(s->write_buffer);
+  gpr_free(s->url);
+  gpr_mu_destroy(&s->recv_mu);
+  if (and_free_memory) {
+    gpr_free(and_free_memory);
+  }
+}
+
+static void destroy_transport(grpc_exec_ctx *exec_ctx, grpc_transport *gt) {
+  grpc_cronet_transport *ct = (grpc_cronet_transport *)gt;
+  gpr_free(ct->host);
+  if (grpc_cronet_trace) {
+    gpr_log(GPR_DEBUG, "Destroy transport");
+  }
+}
+
+const grpc_transport_vtable grpc_cronet_vtable = {
+    sizeof(stream_obj),     "cronet_http",     init_stream,
+    set_pollset_do_nothing, perform_stream_op, NULL,
+    destroy_stream,         destroy_transport, NULL};
diff --git a/src/python/grpcio/grpc/_cython/imports.generated.c b/src/python/grpcio/grpc/_cython/imports.generated.c
index f0a40dbb35c54ebec079ac392fe5482eba768dd1..09551472b5f4bb7fd65c0cc36726a8d8eff3af7b 100644
--- a/src/python/grpcio/grpc/_cython/imports.generated.c
+++ b/src/python/grpcio/grpc/_cython/imports.generated.c
@@ -125,6 +125,7 @@ grpc_header_key_is_legal_type grpc_header_key_is_legal_import;
 grpc_header_nonbin_value_is_legal_type grpc_header_nonbin_value_is_legal_import;
 grpc_is_binary_header_type grpc_is_binary_header_import;
 grpc_call_error_to_string_type grpc_call_error_to_string_import;
+grpc_cronet_secure_channel_create_type grpc_cronet_secure_channel_create_import;
 grpc_auth_property_iterator_next_type grpc_auth_property_iterator_next_import;
 grpc_auth_context_property_iterator_type grpc_auth_context_property_iterator_import;
 grpc_auth_context_peer_identity_type grpc_auth_context_peer_identity_import;
@@ -395,6 +396,7 @@ void pygrpc_load_imports(HMODULE library) {
   grpc_header_nonbin_value_is_legal_import = (grpc_header_nonbin_value_is_legal_type) GetProcAddress(library, "grpc_header_nonbin_value_is_legal");
   grpc_is_binary_header_import = (grpc_is_binary_header_type) GetProcAddress(library, "grpc_is_binary_header");
   grpc_call_error_to_string_import = (grpc_call_error_to_string_type) GetProcAddress(library, "grpc_call_error_to_string");
+  grpc_cronet_secure_channel_create_import = (grpc_cronet_secure_channel_create_type) GetProcAddress(library, "grpc_cronet_secure_channel_create");
   grpc_auth_property_iterator_next_import = (grpc_auth_property_iterator_next_type) GetProcAddress(library, "grpc_auth_property_iterator_next");
   grpc_auth_context_property_iterator_import = (grpc_auth_context_property_iterator_type) GetProcAddress(library, "grpc_auth_context_property_iterator");
   grpc_auth_context_peer_identity_import = (grpc_auth_context_peer_identity_type) GetProcAddress(library, "grpc_auth_context_peer_identity");
diff --git a/src/python/grpcio/grpc/_cython/imports.generated.h b/src/python/grpcio/grpc/_cython/imports.generated.h
index d5e810b7cf47bdcf6f1689b3405deb355254f2a9..54c8aaad13ebbc23deea4468f11f6c3e9caa99ba 100644
--- a/src/python/grpcio/grpc/_cython/imports.generated.h
+++ b/src/python/grpcio/grpc/_cython/imports.generated.h
@@ -43,6 +43,7 @@
 #include <grpc/census.h>
 #include <grpc/compression.h>
 #include <grpc/grpc.h>
+#include <grpc/grpc_cronet.h>
 #include <grpc/grpc_security.h>
 #include <grpc/impl/codegen/alloc.h>
 #include <grpc/impl/codegen/byte_buffer.h>
@@ -325,6 +326,9 @@ extern grpc_is_binary_header_type grpc_is_binary_header_import;
 typedef const char *(*grpc_call_error_to_string_type)(grpc_call_error error);
 extern grpc_call_error_to_string_type grpc_call_error_to_string_import;
 #define grpc_call_error_to_string grpc_call_error_to_string_import
+typedef grpc_channel *(*grpc_cronet_secure_channel_create_type)(void *engine, const char *target, const grpc_channel_args *args, void *reserved);
+extern grpc_cronet_secure_channel_create_type grpc_cronet_secure_channel_create_import;
+#define grpc_cronet_secure_channel_create grpc_cronet_secure_channel_create_import
 typedef const grpc_auth_property *(*grpc_auth_property_iterator_next_type)(grpc_auth_property_iterator *it);
 extern grpc_auth_property_iterator_next_type grpc_auth_property_iterator_next_import;
 #define grpc_auth_property_iterator_next grpc_auth_property_iterator_next_import
diff --git a/src/python/grpcio/grpc_core_dependencies.py b/src/python/grpcio/grpc_core_dependencies.py
index 4b98dc1a133ca732f289e042a53b5553dcab73b7..c6af69360dc5debe574ff6561ed9c4a813084b41 100644
--- a/src/python/grpcio/grpc_core_dependencies.py
+++ b/src/python/grpcio/grpc_core_dependencies.py
@@ -222,6 +222,9 @@ CORE_SOURCE_FILES = [
   'src/core/ext/client_config/uri_parser.c',
   'src/core/ext/transport/chttp2/server/insecure/server_chttp2.c',
   'src/core/ext/transport/chttp2/client/insecure/channel_create.c',
+  'src/core/ext/transport/cronet/client/secure/cronet_channel_create.c',
+  'src/core/ext/transport/cronet/transport/cronet_api_dummy.c',
+  'src/core/ext/transport/cronet/transport/cronet_transport.c',
   'src/core/ext/lb_policy/grpclb/load_balancer_api.c',
   'src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c',
   'third_party/nanopb/pb_common.c',
diff --git a/src/ruby/ext/grpc/rb_grpc_imports.generated.c b/src/ruby/ext/grpc/rb_grpc_imports.generated.c
index bc43f9d36b57aef34a7971d9cf4750474e060ca5..cebbe8c40feba774187743616512b427f310a4b8 100644
--- a/src/ruby/ext/grpc/rb_grpc_imports.generated.c
+++ b/src/ruby/ext/grpc/rb_grpc_imports.generated.c
@@ -125,6 +125,7 @@ grpc_header_key_is_legal_type grpc_header_key_is_legal_import;
 grpc_header_nonbin_value_is_legal_type grpc_header_nonbin_value_is_legal_import;
 grpc_is_binary_header_type grpc_is_binary_header_import;
 grpc_call_error_to_string_type grpc_call_error_to_string_import;
+grpc_cronet_secure_channel_create_type grpc_cronet_secure_channel_create_import;
 grpc_auth_property_iterator_next_type grpc_auth_property_iterator_next_import;
 grpc_auth_context_property_iterator_type grpc_auth_context_property_iterator_import;
 grpc_auth_context_peer_identity_type grpc_auth_context_peer_identity_import;
@@ -391,6 +392,7 @@ void grpc_rb_load_imports(HMODULE library) {
   grpc_header_nonbin_value_is_legal_import = (grpc_header_nonbin_value_is_legal_type) GetProcAddress(library, "grpc_header_nonbin_value_is_legal");
   grpc_is_binary_header_import = (grpc_is_binary_header_type) GetProcAddress(library, "grpc_is_binary_header");
   grpc_call_error_to_string_import = (grpc_call_error_to_string_type) GetProcAddress(library, "grpc_call_error_to_string");
+  grpc_cronet_secure_channel_create_import = (grpc_cronet_secure_channel_create_type) GetProcAddress(library, "grpc_cronet_secure_channel_create");
   grpc_auth_property_iterator_next_import = (grpc_auth_property_iterator_next_type) GetProcAddress(library, "grpc_auth_property_iterator_next");
   grpc_auth_context_property_iterator_import = (grpc_auth_context_property_iterator_type) GetProcAddress(library, "grpc_auth_context_property_iterator");
   grpc_auth_context_peer_identity_import = (grpc_auth_context_peer_identity_type) GetProcAddress(library, "grpc_auth_context_peer_identity");
diff --git a/src/ruby/ext/grpc/rb_grpc_imports.generated.h b/src/ruby/ext/grpc/rb_grpc_imports.generated.h
index b67361ca25b96988054831aec05c924aa73017b9..d7ea6c574c8b8952725a7b2450677049373da521 100644
--- a/src/ruby/ext/grpc/rb_grpc_imports.generated.h
+++ b/src/ruby/ext/grpc/rb_grpc_imports.generated.h
@@ -43,6 +43,7 @@
 #include <grpc/census.h>
 #include <grpc/compression.h>
 #include <grpc/grpc.h>
+#include <grpc/grpc_cronet.h>
 #include <grpc/grpc_security.h>
 #include <grpc/impl/codegen/alloc.h>
 #include <grpc/impl/codegen/byte_buffer.h>
@@ -325,6 +326,9 @@ extern grpc_is_binary_header_type grpc_is_binary_header_import;
 typedef const char *(*grpc_call_error_to_string_type)(grpc_call_error error);
 extern grpc_call_error_to_string_type grpc_call_error_to_string_import;
 #define grpc_call_error_to_string grpc_call_error_to_string_import
+typedef grpc_channel *(*grpc_cronet_secure_channel_create_type)(void *engine, const char *target, const grpc_channel_args *args, void *reserved);
+extern grpc_cronet_secure_channel_create_type grpc_cronet_secure_channel_create_import;
+#define grpc_cronet_secure_channel_create grpc_cronet_secure_channel_create_import
 typedef const grpc_auth_property *(*grpc_auth_property_iterator_next_type)(grpc_auth_property_iterator *it);
 extern grpc_auth_property_iterator_next_type grpc_auth_property_iterator_next_import;
 #define grpc_auth_property_iterator_next grpc_auth_property_iterator_next_import
diff --git a/test/core/surface/public_headers_must_be_c89.c b/test/core/surface/public_headers_must_be_c89.c
index 3eeb55d033dcaa296d15bf1a368ad378a60b8296..fd6ff2c26f5ecca7a8654232a6fdf056370f446b 100644
--- a/test/core/surface/public_headers_must_be_c89.c
+++ b/test/core/surface/public_headers_must_be_c89.c
@@ -36,6 +36,7 @@
 #include <grpc/census.h>
 #include <grpc/compression.h>
 #include <grpc/grpc.h>
+#include <grpc/grpc_cronet.h>
 #include <grpc/grpc_security.h>
 #include <grpc/grpc_security_constants.h>
 #include <grpc/impl/codegen/alloc.h>
diff --git a/third_party/objective_c/Cronet/cronet_c_for_grpc.h b/third_party/objective_c/Cronet/cronet_c_for_grpc.h
new file mode 100644
index 0000000000000000000000000000000000000000..15a511aebd0b3d751b4f13127d8c51b289a89b95
--- /dev/null
+++ b/third_party/objective_c/Cronet/cronet_c_for_grpc.h
@@ -0,0 +1,202 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_CRONET_IOS_CRONET_C_FOR_GRPC_H_
+#define COMPONENTS_CRONET_IOS_CRONET_C_FOR_GRPC_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stddef.h>
+
+/* Cronet Engine API. */
+
+/* Opaque object representing Cronet Engine. Created and configured outside
+ * of this API to facilitate sharing with other components */
+typedef struct cronet_engine { void* obj; } cronet_engine;
+
+void cronet_engine_add_quic_hint(cronet_engine* engine,
+                                 const char* host,
+                                 int port,
+                                 int alternate_port);
+
+/* Cronet Bidirectional Stream API */
+
+/* Opaque object representing Cronet Bidirectional Stream. */
+typedef struct cronet_bidirectional_stream {
+  void* obj;
+  void* annotation;
+} cronet_bidirectional_stream;
+
+/* A single request or response header element. */
+typedef struct cronet_bidirectional_stream_header {
+  const char* key;
+  const char* value;
+} cronet_bidirectional_stream_header;
+
+/* Array of request or response headers or trailers. */
+typedef struct cronet_bidirectional_stream_header_array {
+  size_t count;
+  size_t capacity;
+  cronet_bidirectional_stream_header* headers;
+} cronet_bidirectional_stream_header_array;
+
+/* Set of callbacks used to receive callbacks from bidirectional stream. */
+typedef struct cronet_bidirectional_stream_callback {
+  /* Invoked when request headers are sent. Indicates that stream has initiated
+   * the request. Consumer may call cronet_bidirectional_stream_write() to start
+   * writing data.
+   */
+  void (*on_request_headers_sent)(cronet_bidirectional_stream* stream);
+
+  /* Invoked when initial response headers are received.
+   * Consumer must call cronet_bidirectional_stream_read() to start reading.
+   * Consumer may call cronet_bidirectional_stream_write() to start writing or
+   * close the stream. Contents of |headers| is valid for duration of the call.
+   */
+  void (*on_response_headers_received)(
+      cronet_bidirectional_stream* stream,
+      const cronet_bidirectional_stream_header_array* headers,
+      const char* negotiated_protocol);
+
+  /* Invoked when data is read into the buffer passed to
+   * cronet_bidirectional_stream_read(). Only part of the buffer may be
+   * populated. To continue reading, call cronet_bidirectional_stream_read().
+   * It may be invoked after on_response_trailers_received()}, if there was
+   * pending read data before trailers were received.
+   *
+   * If count is 0, it means the remote side has signaled that it will send no
+   * more data; future calls to cronet_bidirectional_stream_read() will result
+   * in the on_data_read() callback or on_succeded() callback if
+   * cronet_bidirectional_stream_write() was invoked with end_of_stream set to
+   * true.
+   */
+  void (*on_read_completed)(cronet_bidirectional_stream* stream,
+                            char* data,
+                            int count);
+
+  /**
+   * Invoked when all data passed to cronet_bidirectional_stream_write() is
+   * sent.
+   * To continue writing, call cronet_bidirectional_stream_write().
+   */
+  void (*on_write_completed)(cronet_bidirectional_stream* stream,
+                             const char* data);
+
+  /* Invoked when trailers are received before closing the stream. Only invoked
+   * when server sends trailers, which it may not. May be invoked while there is
+   * read data remaining in local buffer. Contents of |trailers| is valid for
+   * duration of the call.
+   */
+  void (*on_response_trailers_received)(
+      cronet_bidirectional_stream* stream,
+      const cronet_bidirectional_stream_header_array* trailers);
+
+  /**
+   * Invoked when there is no data to be read or written and the stream is
+   * closed successfully remotely and locally. Once invoked, no further callback
+   * methods will be invoked.
+   */
+  void (*on_succeded)(cronet_bidirectional_stream* stream);
+
+  /**
+   * Invoked if the stream failed for any reason after
+   * cronet_bidirectional_stream_start(). HTTP/2 error codes are
+   * mapped to chrome net error codes. Once invoked, no further callback methods
+   * will be invoked.
+   */
+  void (*on_failed)(cronet_bidirectional_stream* stream, int net_error);
+
+  /**
+   * Invoked if the stream was canceled via
+   * cronet_bidirectional_stream_cancel(). Once invoked, no further callback
+   * methods will be invoked.
+   */
+  void (*on_canceled)(cronet_bidirectional_stream* stream);
+} cronet_bidirectional_stream_callback;
+
+/* Create a new stream object that uses |engine| and |callback|. All stream
+ * tasks are performed asynchronously on the |engine| network thread. |callback|
+ * methods are invoked synchronously on the |engine| network thread, but must
+ * not run tasks on the current thread to prevent blocking networking operations
+ * and causing exceptions during shutdown. The |annotation| is stored in
+ * bidirectional stream for arbitrary use by application.
+ *
+ * Returned |cronet_bidirectional_stream*| is owned by the caller, and must be
+ * destroyed using |cronet_bidirectional_stream_destroy|.
+ *
+ * Both |calback| and |engine| must remain valid until stream is destroyed.
+ */
+cronet_bidirectional_stream* cronet_bidirectional_stream_create(
+    cronet_engine* engine,
+    void* annotation,
+    cronet_bidirectional_stream_callback* callback);
+
+/* TBD: The following methods return int. Should it be a custom type? */
+
+/* Destroy stream object. Destroy could be called from any thread, including
+ * network thread, but is posted, so |stream| is valid until calling task is
+ * complete.
+ */
+int cronet_bidirectional_stream_destroy(cronet_bidirectional_stream* stream);
+
+/* Start the stream by sending request to |url| using |method| and |headers|. If
+ * |end_of_stream| is true, then no data is expected to be written.
+ */
+int cronet_bidirectional_stream_start(
+    cronet_bidirectional_stream* stream,
+    const char* url,
+    int priority,
+    const char* method,
+    const cronet_bidirectional_stream_header_array* headers,
+    bool end_of_stream);
+
+/* Read response data into |buffer| of |capacity| length. Must only be called at
+ * most once in response to each invocation of the
+ * on_response_headers_received() and on_read_completed() methods of the
+ * cronet_bidirectional_stream_callback.
+ * Each call will result in an invocation of one of the callback's
+ * on_read_completed  method if data is read, its on_succeeded() method if
+ * the stream is closed, or its on_failed() method if there's an error.
+ */
+int cronet_bidirectional_stream_read(cronet_bidirectional_stream* stream,
+                                     char* buffer,
+                                     int capacity);
+
+/* Read response data into |buffer| of |capacity| length. Must only be called at
+ * most once in response to each invocation of the
+ * on_response_headers_received() and on_read_completed() methods of the
+ * cronet_bidirectional_stream_callback.
+ * Each call will result in an invocation of one of the callback's
+ * on_read_completed  method if data is read, its on_succeeded() method if
+ * the stream is closed, or its on_failed() method if there's an error.
+ */
+int cronet_bidirectional_stream_write(cronet_bidirectional_stream* stream,
+                                      const char* buffer,
+                                      int count,
+                                      bool end_of_stream);
+
+/* Cancels the stream. Can be called at any time after
+ * cronet_bidirectional_stream_start(). The on_canceled() method of
+ * cronet_bidirectional_stream_callback will be invoked when cancelation
+ * is complete and no further callback methods will be invoked. If the
+ * stream has completed or has not started, calling
+ * cronet_bidirectional_stream_cancel() has no effect and on_canceled() will not
+ * be  invoked. At most one callback method may be invoked after
+ * cronet_bidirectional_stream_cancel() has completed.
+ */
+int cronet_bidirectional_stream_cancel(cronet_bidirectional_stream* stream);
+
+/* Returns true if the |stream| was successfully started and is now done
+ * (succeeded, canceled, or failed).
+ * Returns false if the |stream| stream is not yet started or is in progress.
+ */
+bool cronet_bidirectional_stream_is_done(cronet_bidirectional_stream* stream);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif  // COMPONENTS_CRONET_IOS_CRONET_C_FOR_GRPC_H_
diff --git a/tools/doxygen/Doxyfile.core b/tools/doxygen/Doxyfile.core
index eed84252cc23ee60ac280f3166fd3f003b8af68a..aabca410dabb8818929fa53d454763212070997b 100644
--- a/tools/doxygen/Doxyfile.core
+++ b/tools/doxygen/Doxyfile.core
@@ -786,6 +786,7 @@ include/grpc/impl/codegen/sync_generic.h \
 include/grpc/impl/codegen/sync_posix.h \
 include/grpc/impl/codegen/sync_win32.h \
 include/grpc/impl/codegen/time.h \
+include/grpc/grpc_cronet.h \
 include/grpc/grpc_security.h \
 include/grpc/grpc_security_constants.h \
 include/grpc/census.h \
diff --git a/tools/doxygen/Doxyfile.core.internal b/tools/doxygen/Doxyfile.core.internal
index 7e0d5ebd37fde345f79e7fb432b984b2a292b726..bcaaaf8e0b65d6ed3f2d67f56c5cc2caadfbf335 100644
--- a/tools/doxygen/Doxyfile.core.internal
+++ b/tools/doxygen/Doxyfile.core.internal
@@ -786,6 +786,7 @@ include/grpc/impl/codegen/sync_generic.h \
 include/grpc/impl/codegen/sync_posix.h \
 include/grpc/impl/codegen/sync_win32.h \
 include/grpc/impl/codegen/time.h \
+include/grpc/grpc_cronet.h \
 include/grpc/grpc_security.h \
 include/grpc/grpc_security_constants.h \
 include/grpc/census.h \
@@ -913,6 +914,7 @@ src/core/ext/client_config/subchannel.h \
 src/core/ext/client_config/subchannel_call_holder.h \
 src/core/ext/client_config/subchannel_index.h \
 src/core/ext/client_config/uri_parser.h \
+third_party/objective_c/Cronet/cronet_c_for_grpc.h \
 src/core/ext/lb_policy/grpclb/load_balancer_api.h \
 src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h \
 third_party/nanopb/pb.h \
@@ -1071,6 +1073,9 @@ src/core/ext/client_config/subchannel_index.c \
 src/core/ext/client_config/uri_parser.c \
 src/core/ext/transport/chttp2/server/insecure/server_chttp2.c \
 src/core/ext/transport/chttp2/client/insecure/channel_create.c \
+src/core/ext/transport/cronet/client/secure/cronet_channel_create.c \
+src/core/ext/transport/cronet/transport/cronet_api_dummy.c \
+src/core/ext/transport/cronet/transport/cronet_transport.c \
 src/core/ext/lb_policy/grpclb/load_balancer_api.c \
 src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c \
 third_party/nanopb/pb_common.c \
diff --git a/tools/run_tests/sources_and_headers.json b/tools/run_tests/sources_and_headers.json
index b36f0a8ca8ef2c8a62ed1ea6d3fe3bcd4d247d05..78106a5277ba8603745903ac0ffaa0fb9d12ee88 100644
--- a/tools/run_tests/sources_and_headers.json
+++ b/tools/run_tests/sources_and_headers.json
@@ -4175,7 +4175,8 @@
       "grpc_transport_chttp2_client_insecure", 
       "grpc_transport_chttp2_client_secure", 
       "grpc_transport_chttp2_server_insecure", 
-      "grpc_transport_chttp2_server_secure"
+      "grpc_transport_chttp2_server_secure", 
+      "grpc_transport_cronet_client_secure"
     ], 
     "headers": [], 
     "language": "c", 
@@ -6049,6 +6050,7 @@
       "tsi"
     ], 
     "headers": [
+      "include/grpc/grpc_cronet.h", 
       "include/grpc/grpc_security.h", 
       "include/grpc/grpc_security_constants.h", 
       "src/core/lib/security/auth_filters.h", 
@@ -6064,6 +6066,7 @@
     "language": "c", 
     "name": "grpc_secure", 
     "src": [
+      "include/grpc/grpc_cronet.h", 
       "include/grpc/grpc_security.h", 
       "include/grpc/grpc_security_constants.h", 
       "src/core/lib/http/httpcli_security_connector.c", 
@@ -6299,6 +6302,24 @@
     "third_party": false, 
     "type": "filegroup"
   }, 
+  {
+    "deps": [
+      "grpc_base", 
+      "grpc_transport_chttp2"
+    ], 
+    "headers": [
+      "third_party/objective_c/Cronet/cronet_c_for_grpc.h"
+    ], 
+    "language": "c", 
+    "name": "grpc_transport_cronet_client_secure", 
+    "src": [
+      "src/core/ext/transport/cronet/client/secure/cronet_channel_create.c", 
+      "src/core/ext/transport/cronet/transport/cronet_api_dummy.c", 
+      "src/core/ext/transport/cronet/transport/cronet_transport.c"
+    ], 
+    "third_party": false, 
+    "type": "filegroup"
+  }, 
   {
     "deps": [], 
     "headers": [
diff --git a/vsprojects/vcxproj/grpc/grpc.vcxproj b/vsprojects/vcxproj/grpc/grpc.vcxproj
index 6a2843e37c9e7af850544eeb0ea6f29e549297d9..75c1288c8967b52d0da6e468f1938da72638edb4 100644
--- a/vsprojects/vcxproj/grpc/grpc.vcxproj
+++ b/vsprojects/vcxproj/grpc/grpc.vcxproj
@@ -293,6 +293,7 @@
     <ClInclude Include="$(SolutionDir)\..\include\grpc\impl\codegen\sync_posix.h" />
     <ClInclude Include="$(SolutionDir)\..\include\grpc\impl\codegen\sync_win32.h" />
     <ClInclude Include="$(SolutionDir)\..\include\grpc\impl\codegen\time.h" />
+    <ClInclude Include="$(SolutionDir)\..\include\grpc\grpc_cronet.h" />
     <ClInclude Include="$(SolutionDir)\..\include\grpc\grpc_security.h" />
     <ClInclude Include="$(SolutionDir)\..\include\grpc\grpc_security_constants.h" />
     <ClInclude Include="$(SolutionDir)\..\include\grpc\census.h" />
@@ -422,6 +423,7 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_config\subchannel_call_holder.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_config\subchannel_index.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_config\uri_parser.h" />
+    <ClInclude Include="$(SolutionDir)\..\third_party\objective_c\Cronet\cronet_c_for_grpc.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\lb_policy\grpclb\load_balancer_api.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\lb_policy\grpclb\proto\grpc\lb\v1\load_balancer.pb.h" />
     <ClInclude Include="$(SolutionDir)\..\third_party\nanopb\pb.h" />
@@ -728,6 +730,12 @@
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\transport\chttp2\client\insecure\channel_create.c">
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\transport\cronet\client\secure\cronet_channel_create.c">
+    </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\transport\cronet\transport\cronet_api_dummy.c">
+    </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\transport\cronet\transport\cronet_transport.c">
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\lb_policy\grpclb\load_balancer_api.c">
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\lb_policy\grpclb\proto\grpc\lb\v1\load_balancer.pb.c">
diff --git a/vsprojects/vcxproj/grpc/grpc.vcxproj.filters b/vsprojects/vcxproj/grpc/grpc.vcxproj.filters
index 7d53be719cf8b17e37ac3c451c48314729c4d2f4..d576b14877f3c53477ee5a319900b78e3ae243de 100644
--- a/vsprojects/vcxproj/grpc/grpc.vcxproj.filters
+++ b/vsprojects/vcxproj/grpc/grpc.vcxproj.filters
@@ -439,6 +439,15 @@
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\transport\chttp2\client\insecure\channel_create.c">
       <Filter>src\core\ext\transport\chttp2\client\insecure</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\transport\cronet\client\secure\cronet_channel_create.c">
+      <Filter>src\core\ext\transport\cronet\client\secure</Filter>
+    </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\transport\cronet\transport\cronet_api_dummy.c">
+      <Filter>src\core\ext\transport\cronet\transport</Filter>
+    </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\transport\cronet\transport\cronet_transport.c">
+      <Filter>src\core\ext\transport\cronet\transport</Filter>
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\lb_policy\grpclb\load_balancer_api.c">
       <Filter>src\core\ext\lb_policy\grpclb</Filter>
     </ClCompile>
@@ -576,6 +585,9 @@
     <ClInclude Include="$(SolutionDir)\..\include\grpc\impl\codegen\time.h">
       <Filter>include\grpc\impl\codegen</Filter>
     </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\include\grpc\grpc_cronet.h">
+      <Filter>include\grpc</Filter>
+    </ClInclude>
     <ClInclude Include="$(SolutionDir)\..\include\grpc\grpc_security.h">
       <Filter>include\grpc</Filter>
     </ClInclude>
@@ -959,6 +971,9 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_config\uri_parser.h">
       <Filter>src\core\ext\client_config</Filter>
     </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\third_party\objective_c\Cronet\cronet_c_for_grpc.h">
+      <Filter>third_party\objective_c\Cronet</Filter>
+    </ClInclude>
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\lb_policy\grpclb\load_balancer_api.h">
       <Filter>src\core\ext\lb_policy\grpclb</Filter>
     </ClInclude>
@@ -1091,6 +1106,18 @@
     <Filter Include="src\core\ext\transport\chttp2\transport">
       <UniqueIdentifier>{6f34254e-e69f-c9b4-156d-5024bade5408}</UniqueIdentifier>
     </Filter>
+    <Filter Include="src\core\ext\transport\cronet">
+      <UniqueIdentifier>{1e9c85e9-5522-7ef8-0017-7e19990a6194}</UniqueIdentifier>
+    </Filter>
+    <Filter Include="src\core\ext\transport\cronet\client">
+      <UniqueIdentifier>{d0530883-75d9-b5f7-d594-26735a70ac7b}</UniqueIdentifier>
+    </Filter>
+    <Filter Include="src\core\ext\transport\cronet\client\secure">
+      <UniqueIdentifier>{4fa6fe90-b7a8-5c8f-d629-db1e68d89eed}</UniqueIdentifier>
+    </Filter>
+    <Filter Include="src\core\ext\transport\cronet\transport">
+      <UniqueIdentifier>{31518af8-5860-6d0d-ff78-4059fce29ec2}</UniqueIdentifier>
+    </Filter>
     <Filter Include="src\core\lib">
       <UniqueIdentifier>{5b2ded3f-84a5-f6b4-2060-286c7d1dc945}</UniqueIdentifier>
     </Filter>
@@ -1133,6 +1160,12 @@
     <Filter Include="third_party\nanopb">
       <UniqueIdentifier>{93d6596d-330c-1d27-6f84-3c840e57869e}</UniqueIdentifier>
     </Filter>
+    <Filter Include="third_party\objective_c">
+      <UniqueIdentifier>{3a56a516-857e-d2aa-95cc-11685baf4e8c}</UniqueIdentifier>
+    </Filter>
+    <Filter Include="third_party\objective_c\Cronet">
+      <UniqueIdentifier>{a165c6e3-0776-6f40-7351-d7865668e220}</UniqueIdentifier>
+    </Filter>
   </ItemGroup>
 </Project>