Setting directory permissions on one workarea

System

Hi,

Solaris-8
TS 552
Can I set different group permissions for the data categories under one workarea. I want to restrict one user from viewing & editing files created by another user in another category.

e.g.
WA-1
Data Cat-1 (view.edit permission only for user-1)
Data Type-1
Data Cat-2 (view.edit permission only for user-2)
Data Type-2

I think possible with setting group permission for specific data cat folder, from unix command prompt. If yes what may the cons for this.

!Thanx