Directory Sharing Problem With NT

I am running a Nt Network and setting up users with mapped drives. Is there any way to map a drive to a directory on my server and only show the sub-directorys that the user has access too… only other way would be to have a bunch of directories that the users can’t get too (Access Denyed) and only 1 or 2 directoies that they can access. I have user groups assigned to each sub-directory. Some users belong to more than one group and their for would need to see a couple of sub directoies. othersonly belong to one group.If you need more info, please ask! I have looked everywhere for a answer and haven’t found one yet!