diff --git a/composer.json b/composer.json
index c2f9e86..f8af857 100644
--- a/composer.json
+++ b/composer.json
@@ -12,7 +12,7 @@
   ],
   "require": {
     "phing/phing": "~2.9",
-    "drush/drush": "~6.5"
+    "drush/drush": "6.5 - 7.0"
   },
   "autoload": {
     "psr-0": {