diff --git a/composer.json b/composer.json
index 878dc48..d4d8180 100644
--- a/composer.json
+++ b/composer.json
@@ -10,7 +10,7 @@
 		"silverstripe-themes/simple": "3.1.*"
 	},
 	"require-dev": {
-		"phpunit/PHPUnit": "~3.7"
+		"phpunit/PHPUnit": "~4.8"
 	},
 	"extra": {
 		"branch-alias": {