diff --git a/README.md b/README.md
index 7e505f9f1..152ab0157 100644
--- a/README.md
+++ b/README.md
@@ -128,9 +128,16 @@ bin/console fom:user:resetroot
 Run this command to start a local mapbender instance in a docker container using an internal sqlite database.
 
 ```bash
-docker run mapbender/mapbender
+docker run -p 80:8080 mapbender/mapbender
 ```
 
+If you want mapbender to stay up and running in background add the `-d` option.
+
+### ENV variables
+
+You can use environment variables to adjust the configuration of a docker container.
+E.g. the variable `MAPBENDER_DATABASE_URL` is used to setup another database as shown in the next example.
+
 ### external database 
 
 To run a Mapbender docker container configured to use an external database we will use the MAPBENDER_DATABASE_URL environment variable.