The Association of Southeast Asian Nations (ASEAN) is Southeast Asia's primary multilateral organization. Established in 1967, it has grown into one of the world's largest regional fora, representing a strategically important group of 10 nations that spans critical sea lanes and accounts for 5% of U.S. trade. This report discusses U.S. diplomatic, security, trade, and aid ties with ASEAN, analyzes major issues affecting Southeast Asian countries and U.S.-ASEAN relations, and examines ASEAN's relations with other regional powers. Much U.S. engagement with the region occurs at the bilateral level, but this report focuses on multilateral diplomacy. The United States has deep-seated ties in Southeast Asia, and it has viewed ASEAN as a useful organization since its inception during the Cold War. Today, U.S. policy towards ASEAN and Southeast Asia is cast against the backdrop of great power rivalry in East Asia, and particularly China's emergence as an active diplomatic actor in its geographic backyard. Some worry that the United States, preoccupied with other priorities, has been neglectful of ASEAN and of Asian multilateral diplomacy in recent years. The Obama Administration has expressed an intent to work more closely with multilateral organizations, particularly ASEAN. A number of steps in this direction include Secretary of State Hillary Clinton's visit to the ASEAN Secretariat in Jakarta in February 2009, the U.S. accession to ASEAN's Treaty of Amity and Cooperation (TAC) in July 2009, and President Obama's attendance at an ASEAN leaders meeting in November 2009. Congress has frequently played an important role in shaping U.S. diplomatic, security, and economic relations with Southeast Asia and ASEAN. Major U.S. and congressional interests in Southeast Asia include maritime security, the promotion of democracy and human rights, the encouragement of liberal trade and investment regimes, counterterrorism, combating narcotics trafficking, environmental preservation, and many others. In October 2009, Senator Richard Lugar introduced S.Res. 311, calling for the start of discussions on a free trade agreement with ASEAN. In August 2009, Senator Jim Webb visited five countries in mainland Southeast Asia and was the first Member of Congress in ten years to visit Burma. The United States exerts a strong military and economic presence in Southeast Asia, and through diplomacy it seeks to remain a major power--perhaps the major power--in the region. ASEAN, however, has been active in recent years in exploring a variety of diplomatic architectures for East Asia and the Pacific. ASEAN is at the center of several broader security- and trade-related groupings in the Asia-Pacific region, through which it has aimed to maintain regional multi- polarity or a balance of powers among itself and other states including the United States, China, and Japan. ASEAN is also the nexus for discussion of regional economic integration. ASEAN has launched an internal free trade accord, the ASEAN Free Trade Agreement (AFTA), which will go into full effect in 2015. ASEAN has also concluded FTAs with many external trade partners, though not with the United States. ASEAN has also been exploring ways to advance the ultimate creation of a broader European Union-like East Asia Community. Some within the group--but not all--support the inclusion of the United States in such a community. Human rights conditions, particularly in some ASEAN members such as Burma, have long been a source of friction between the organization and the United States. ASEAN's new Charter, enacted in 2007, attempts to bring more pressure to bear upon recalcitrant member states. However, ASEAN still operates on principles of consensus and non-interference in the internal affairs of its members, so it remains unclear how active an actor it will be in this area.