diff --git a/README.md b/README.md
index c81ebf4..54c45ff 100644
--- a/README.md
+++ b/README.md
@@ -33,7 +33,7 @@ List of available configuration options:
 | ---- | ----------- |
 | `SQLALCHEMY_DATABASE_URI` | Database connection string.  e.g: `postgresql://user:password@localhost/photowall` |
 | `DEBUG` | Enable/disable debug mode |
-| `API_KEYS` | A list of api keys that are used to authenticate to the API |
+| `API_KEYS` | A list of api keys that are used to authenticate to the API. If this list is empty authentication will be disabled. |
 | `ESALES_URL` | URL to the eSales server. If its a cloud cluster it has the format `username:password` |
 | `ESALES_IMPORT_DIR` | XML-files that should be imported to eSales are temporarily stored in this directory. e.g: `/tmp/esales`