diff --git a/gRPC.podspec b/gRPC.podspec
index c056d717c86c38e5e4a6a274034af7d4201064c0..1ee2198125facf81fe57560c112c07b983c549db 100644
--- a/gRPC.podspec
+++ b/gRPC.podspec
@@ -528,6 +528,8 @@ Pod::Spec.new do |s|
                               'src/core/census/rpc_metric_id.h'
 
     ss.header_mappings_dir = '.'
+    # This isn't officially supported in Cocoapods. We've asked for an alternative:
+    # https://github.com/CocoaPods/CocoaPods/issues/4386
     ss.xcconfig = { 'HEADER_SEARCH_PATHS' => '"$(PODS_ROOT)/Headers/Private/gRPC" ' +
                                              '"$(PODS_ROOT)/Headers/Private/gRPC/include"' }