Possible Modules

Is it possible with the any current modules to be able to do the following scenario?

Want to be able to limit access to pages based on groups, and see other users in the organization.

User A is in Group 1 for Organization Z
User B is in Group 2 for Organization Z
User C is in Group 3 for Organization Z
User D is in Group 1 for Organization Y

User A can see pages A, B, C, and D and see all users in Organization Z (similar to a directory view)
User B can see pages A, B, and C and see all users in Organization Z
User C can see pages A and B and see all users in Organization Z
User D can see pages A, B, C, and D and see all users in Organization Y

Thanks