diff --git a/README.md b/README.md
index a86179e..3c161bc 100644
--- a/README.md
+++ b/README.md
@@ -494,7 +494,7 @@ cli.enable_server_certificate_verification(true);
 Zlib Support
 ------------
 
-'gzip' compression is available with `CPPHTTPLIB_ZLIB_SUPPORT`.
+'gzip' compression is available with `CPPHTTPLIB_ZLIB_SUPPORT`. `libz` should be linked.
 
 The server applies gzip compression to the following MIME type contents: