diff --git a/composer.json b/composer.json
index b537d19..8355d9f 100644
--- a/composer.json
+++ b/composer.json
@@ -12,7 +12,7 @@
     ],
     "require": {
         "php": ">=5.3.2",
-        "symfony/symfony": "~3.1"
+        "symfony/symfony": "~3.1 || ~4.0"
     },
     "suggest": {