Commercial Metal Framed Partition Walls?

new guy

I have only done residential contracting in the past, however, have started finishing some commercial office space for a friend. The plans call for the partition walls to be "3 5/8" steel studs spaced 24" O.C. to underside of acoustical ceiling". Does the acoustical ceiling typically run the entire space with the partition walls run up to it? I thought the walls would run up to the deck and the acoustical ceiling hung in each room. If they are only run up to the acoustical ceiling, how are they supported? Any ideas?