The study examines the demand for amphibious capabilities in the Indo-Asia-Pacific region and explores the strategic and operational utility of various models for combined U.S. and Australian amphibious forces. The demand for amphibious capabilities reflects the operational and strategic challenges faced by the U.S. Marine Corps and Australian Defense Forces. Both nations have indicated the importance of deepening their strategic partnership, yet there has been a lack of clarity around the desired outcomes for and priority among the variety of cooperative activities.