diff --git a/tmux.conf b/tmux.conf
index 96c568b..6224b43 100644
--- a/tmux.conf
+++ b/tmux.conf
@@ -1,4 +1,5 @@
 set-option -g prefix C-b # default
+set-window-option -g mode-keys vi
 
 bind r source-file ~/.tmux.conf