diff --git a/CHANGELOG.md b/CHANGELOG.md
index 49488cb..d3f7e87 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,9 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project follows keepalived versioning.
 
 ## [1.4.4] - 2018-04-14
+### Added
+  - Router ID with environment KEEPALIVED_ROUTER_ID #16
+  
 ### Changed
   - Upgrade keepalived version to 1.4.4
 
diff --git a/README.md b/README.md
index c0e0755..993beff 100644
--- a/README.md
+++ b/README.md
@@ -79,6 +79,7 @@ See how to [set your own environment variables](#set-your-own-environment-variab
 - **KEEPALIVED_INTERFACE**: Keepalived network interface. Defaults to `eth0`
 - **KEEPALIVED_PASSWORD**: Keepalived password. Defaults to `d0cker`
 - **KEEPALIVED_PRIORITY** Keepalived node priority. Defaults to `150`
+- **KEEPALIVED_ROUTER_ID** Keepalived virtual router ID. Defaults to `51`
 
 - **KEEPALIVED_UNICAST_PEERS** Keepalived unicast peers. Defaults to :
       - 192.168.1.10