diff --git a/docs/vars.md b/docs/vars.md
index 9797aeac3..36e810e37 100644
--- a/docs/vars.md
+++ b/docs/vars.md
@@ -50,6 +50,7 @@ Kubernetes needs some parameters in order to get deployed. These are the
 following default cluster parameters:
 
 * *cluster_name* - Name of cluster (default is cluster.local)
+* *container_manager* - Container Runtime to install in the nodes (default is docker)
 * *dns_domain* - Name of cluster DNS domain (default is cluster.local)
 * *kube_network_plugin* - Plugin to use for container networking
 * *kube_service_addresses* - Subnet for cluster IPs (default is