Commencement Bay is a bay of Puget Sound in the U.S. state of Washington. The city of Tacoma is located on the bay, with the Port of Tacoma occupying the southeastern end. A line drawn from Point Defiance in the southwest to Browns Point in the northeast serves to mark the generally accepted division between the bay and the open sound. Commencement Bay has become home to one of the most active commercial ports in the world.