diff --git a/src/OAuth2/GrantTypeInterface.php b/src/OAuth2/Grant/GrantTypeInterface.php
similarity index 78%
rename from src/OAuth2/GrantTypeInterface.php
rename to src/OAuth2/Grant/GrantTypeInterface.php
index ce79a6eb..67a389c2 100644
--- a/src/OAuth2/GrantTypeInterface.php
+++ b/src/OAuth2/Grant/GrantTypeInterface.php
@@ -7,4 +7,6 @@ interface GrantTypeInterface
     public function getIdentifier();
 
     public function getResponseType();
+
+    public function completeFlow();
 }