diff --git a/gRPC.podspec b/gRPC.podspec
index c672070d363c211c6b7114331d4361b75758bbb4..b491d02c4afa8ccb0222173cbc9075f6aa58f168 100644
--- a/gRPC.podspec
+++ b/gRPC.podspec
@@ -558,6 +558,8 @@ 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"' }