Abstract: The paper explores the development of Vietnam’s bilateral defense diplomacy with world and regional powers including the United States, India, and Japan, with a particular focus on the period from 2009 to 2018. The paper finds that Vietnam’s multidirectional defense diplomacy is fundamentally shaped by its historical experience, the contemporary shift in the balance of power and the strategic challenges caused by China’s emerging power. By pursuing a multi–polar balance among major partners, Vietnam avoids being pulled into their rivalry, and keeps its non-alignment as well as strategic autonomy. The international defense cooperation has become further deepened and more substantive to satisfy Vietnam’s strategic interests including national security, territorial integrity, economic development and regime legitimacy. However, domestic and geo–strategic constraints, and asymmetrical economic interdependence with China lead this paper to suppose further challenges in the future of Vietnam’s defense diplomacy. Full text available here.