web form 2010 update active directory groups

In an existing vb.net 2010 web form application, I am going to add an web interface for a user to be able to do the following:
1. See what users are assigned to 5 specific active directory groups, and
2. allow the user to update the active directory groups.
Thus can you show me and/or point me to a url that shows me example code on how to allow users to set the active directory groups and to update the active directory groups through the web interface?