diff --git a/oxford_asl.in b/oxford_asl.in
index b98a86c..c4df3fa 100755
--- a/oxford_asl.in
+++ b/oxford_asl.in
@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 # OXFORD_ASL: Converts ASL images in to perfusion maps
 #