diff --git a/docs/using/common.md b/docs/using/common.md
index a9c37ddf..ab44315d 100644
--- a/docs/using/common.md
+++ b/docs/using/common.md
@@ -23,7 +23,7 @@ docker run -d -p 8888:8888 jupyter/base-notebook start-notebook.sh --NotebookApp
 You may instruct the `start-notebook.sh` script to customize the container environment before launching
 the notebook server. You do so by passing arguments to the `docker run` command.
 
-* `-e NB_USER=jovyan` - Instructs the startup script to change the default container username from `jovyan` to the provided value. Causes the script to rename the `jovyan` user home folder.
+* `-e NB_USER=jovyan` - Instructs the startup script to change the default container username from `jovyan` to the provided value. Causes the script to rename the `jovyan` user home folder. For this option to take effect, you must run the container with `--user root` and set the working directory `-w /home/$NB_USER`. This feature is useful when mounting host volumes with specific home folder.
 * `-e NB_UID=1000` - Instructs the startup script to switch the numeric user ID of `$NB_USER` to the given value. This feature is useful when mounting host volumes with specific owner permissions. For this option to take effect, you must run the container with `--user root`. (The startup script will `su $NB_USER` after adjusting the user ID.) You might consider using modern Docker options `--user` and `--group-add` instead. See the last bullet below for details.
 * `-e NB_GID=100` - Instructs the startup script to change the primary group of`$NB_USER` to `$NB_GID` (the new group is added with a name of `$NB_GROUP` if it is defined, otherwise the group is named `$NB_USER`).  This feature is useful when mounting host volumes with specific group permissions. For this option to take effect, you must run the container with `--user root`. (The startup script will `su $NB_USER` after adjusting the group ID.) You might consider using modern Docker options `--user` and `--group-add` instead. See the last bullet below for details.  The user is added to supplemental group `users` (gid 100) in order to allow write access to the home directory and `/opt/conda`.  If you override the user/group logic, ensure the user stays in group `users` if you want them to be able to modify files in the image.
 * `-e NB_GROUP=<name>` - The name used for `$NB_GID`, which defaults to `$NB_USER`.  This is only used if `$NB_GID` is specified and completely optional: there is only cosmetic effect.