I think Domain Access might be useful to you. Alternately, you may be interested in Nate Haug's post on using table prefixing to do single-sign-on: http://www.lullabot.com/articles/drupal-single-sign-across-sub-domains
-Randy
How do I restrict user management in a subdomain environment? For example, I don't want a chapter administrator to view and edit all chapter members across all chapters, but I do want to give that ability to a super admin. I installed the Role Delegation module, but that doesn't restrict viewing the list of all users, it just linits roles when new users are created. Any suggestions? Thanks.
Debra