diff --git a/README.md b/README.md
index cbfc260..25f1365 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,7 @@ focus on classic terminal/modem features and more focus on the needs of
 embedded developers and hackers.
 
 tio was originally created to replace screen for connecting to serial devices
-when used in combination with tmux.
+when used in combination with [tmux](https://tmux.github.io).
 
 ## 2. Usage