diff --git a/README.md b/README.md
index 7358677..cecf256 100644
--- a/README.md
+++ b/README.md
@@ -16,5 +16,6 @@ The configuration is passed by using environment variables.
 * ```DROPBOT_JID``` - JID of the bot account
 * ```DROPBOT_PASSWORD``` - Password of the account
 * ```DROPBOT_NICKNAME``` - MUC nickname (defaults to Dropbot)
+* ```DROPBOT_ROOMS``` - List of MUC rooms to join, seperated by commas
 * ```DROPBOT_CMD_PREFIX``` - Prefix of MUC channel commands (defaults to !)
 * ```DROPBOT_KOS_URL``` - URL of the CVA KOS API service (defaults to http://kos.cva-eve.org/api/)