diff --git a/README.md b/README.md
index 2a40b98..47a6cc5 100644
--- a/README.md
+++ b/README.md
@@ -70,6 +70,8 @@ To set accounts & passwords:
 * $ sudo hkexpasswd/hkexpasswd -u joebloggs
 * $ <enter a password, enter again to confirm>
 
+WARNING WARNING WARNING: the -d debug flag will echo passwords to the log/console!
+
 Running Clent and Server
 --
 In separate shells A and B: