diff --git a/README.md b/README.md
index 7f0e131ef..99a24c1ad 100644
--- a/README.md
+++ b/README.md
@@ -33,8 +33,11 @@ To deploy the cluster you can use :
     cat inventory/mycluster/group_vars/all/all.yml
     cat inventory/mycluster/group_vars/k8s-cluster/k8s-cluster.yml
 
-    # Deploy Kubespray with Ansible Playbook
-    ansible-playbook -i inventory/mycluster/hosts.ini cluster.yml
+    # Deploy Kubespray with Ansible Playbook - run the playbook as root
+    # The option `-b` is required, as for example writing SSL keys in /etc/,
+    # installing packages and interacting with various systemd daemons.
+    # Without -b the playbook will fail to run!
+    ansible-playbook -i inventory/mycluster/hosts.ini --become --become-user=root cluster.yml
 
 Note: When Ansible is already installed via system packages on the control machine, other python packages installed via `sudo pip install -r requirements.txt` will go to a different directory tree (e.g. `/usr/local/lib/python2.7/dist-packages` on Ubuntu) from Ansible's (e.g. `/usr/lib/python2.7/dist-packages/ansible` still on Ubuntu).
 As a consequence, `ansible-playbook` command will fail with: