diff --git a/composer.json b/composer.json
index 2943f1b..a0fb16b 100644
--- a/composer.json
+++ b/composer.json
@@ -17,7 +17,7 @@
         "rhumsaa/uuid": "2.8.*"
     },
     "require-dev": {
-        "phpunit/phpunit": "4.3.*",
+        "phpunit/phpunit": "4.5.*",
         "satooshi/php-coveralls": "dev-master"
     },
     "homepage": "http://snowplowanalytics.com/",