diff --git a/.tmux.conf b/.tmux.conf
index 93bb310..f130afb 100644
--- a/.tmux.conf
+++ b/.tmux.conf
@@ -83,6 +83,9 @@ bind C-a last-window
 # Bigger history
 set -g history-limit 10000
 
+# Automatically copy a handful of useful environment variables so you won't loose ssh-agent for example
+set -g update-environment -r
+
 # Fix for shift-keys with Fn; needs correct terminfo too
 setw -g xterm-keys on