diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index fb9a40c..cf18ea7 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -789,6 +789,7 @@
 
 /**
  * \brief          Initialize an SSL context
+ *                 (An individual SSL context is not thread-safe)
  *
  * \param ssl      SSL context
  *