diff --git a/architecture.md b/architecture.md
index 95e3aef46be..91043892ac0 100644
--- a/architecture.md
+++ b/architecture.md
@@ -17,8 +17,8 @@ plane.
 The Kubernetes node has the services necessary to run application containers and
 be managed from the master systems.
 
-Each node runs Docker, of course.  Docker takes care of the details of
-downloading images and running containers.
+Each node runs a container runtime (like Docker, rkt or Hyper). The container
+runtime is responsible for downloading images and running containers.
 
 ### `kubelet`