diff --git a/doc/cpp-style-guide.md b/doc/cpp-style-guide.md
index b89ba99e4d7e70351295beb924c284c8115c4f01..271ff3984c3585de5d85b61870e08dfb2957b37d 100644
--- a/doc/cpp-style-guide.md
+++ b/doc/cpp-style-guide.md
@@ -78,4 +78,5 @@ default capture). Other C++ functional features such as
   is that many of these collection implementations assume a copy
   constructor
   to be available.
-  
+- Don't use `std::this_thread` . Use `gpr_sleep_until` for sleeping a thread.
+