diff --git a/composer.json b/composer.json
index 2c470b5..9b71316 100644
--- a/composer.json
+++ b/composer.json
@@ -11,6 +11,6 @@
     "source": "http://cgit.drupalcode.org/campaignmonitor"
   },
   "require": {
-    "campaignmonitor/createsend-php": "{version}"
+    "campaignmonitor/createsend-php": "^5.0.2"
   }
 }