diff --git a/compose/cli/main.py b/compose/cli/main.py
index 781c5762..a7210c30 100644
--- a/compose/cli/main.py
+++ b/compose/cli/main.py
@@ -344,6 +344,11 @@ class TopLevelCommand(DocoptCommand):
         """
         Remove stopped service containers.
 
+        By default, volumes attached to containers will not be removed. You can see all
+        volumes with `docker volume ls`.
+
+        Any data which is not in a volume will be lost.
+
         Usage: rm [options] [SERVICE...]
 
         Options:
diff --git a/docs/reference/rm.md b/docs/reference/rm.md
index 2ed959e4..f8479224 100644
--- a/docs/reference/rm.md
+++ b/docs/reference/rm.md
@@ -20,3 +20,8 @@ Options:
 ```
 
 Removes stopped service containers.
+
+By default, volumes attached to containers will not be removed. You can see all
+volumes with `docker volume ls`.
+
+Any data which is not in a volume will be lost.