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. The Port of Tacoma is the main port facility.

Tacoma is the county seat of Pierce County, Washington, United States. A port city, it is situated along Washington's Puget Sound, 32 miles (51 km) southwest of Seattle, 36 miles (58 km) southwest of Bellevue, 31 miles (50 km) northeast of the state capital, Olympia, 58 miles (93 km) northwest of Mount Rainier National Park, and 80 miles (130 km) east of Olympic National Park. The city's population was 219,346 at the time of the 2020 census. Tacoma is the second-largest city in the Puget Sound area and the third-most populous in the state. Tacoma also serves as the center of business activity for the South Sound region, which has a population of about 1 million.