diff --git a/nvm.sh b/nvm.sh
index 88d391f..8a35a9d 100644
--- a/nvm.sh
+++ b/nvm.sh
@@ -1,3 +1,4 @@
+#!/bin/bash
 # Node Version Manager
 # Implemented as a POSIX-compliant function
 # Should work on sh, dash, bash, ksh, zsh