The 10-member Association of Southeast Asian Nations, ASEAN, is arguably the most durable and successful regional grouping in the developing world. Established in 1967, it has contributed greatly to regional harmony and prosperity. ASEAN is characterized by great internal diversity, generally high economic growth, and a reluctance to establish a strong supranational structure. Beginning in 1976—with its five original members—ASEAN began to move toward economic cooperation and integration, initially with a focus on merchandise trade. In the 1990s, it added focus on services, investment, and labor. And in the past decade—now including all of Southeast Asia—ASEAN broadened cooperation on macroeconomic and financial issues, many of these together with its Northeast Asian neighbors—the "Plus 3" of the People's Republic of China, Japan, and the Republic of Korea. Members adopted what may appear to be formal preferential trade arrangements. But in practice these are usually multilateralized. ASEAN informally embraces what is sometimes termed "open regionalism." However, there is little likelihood in the foreseeable future that this will evolve into a deep EU-style economic integration behind a common external trade regime, despite a commitment to forming an ASEAN Economic Community beginning 2015.