Model user roles after another user's roles

I'm not quite sure where to post this so I'll start here.

We have a fairly complex access control system for Drupal with many users and many roles. Other systems I have worked with allow creating a new user that has the same roles as another user so that the new user's roles don't have to be added manually.

I have done a quick search and did not come up with anything that would do this. I would like to be able to model a user's roles after another user's roles or perhaps create groups of users that would all have the same roles.

Any help appreciated.