Yes it can be done.
What kind of server are you dealing with?
Each platform has its own things.
The general guideline would be that each user has their own login and workspace, which is protected by OS level security features.
SAS supports the concept of SASUSER, but you have to be careful, because SASUSER is typically a persistent library, unlike WORK. But, it is possible to have a unique WORK directory/libary for each user. For Windows and Unix, for each account, either set the SAS_User_Config environment variable, or have a sasV9.cfg file in the user's "$HOME" directory. For a mainframe, control would be through RACF.