The ADB is a regional development bank to promote social and economic development in Asia. The bank is headquartered in Metro Manila, Philippines and maintains 39 field offices around the world.
The bank was established on 19 December 1966 and admits the members of the UN Economic and Social Commission for Asia and the Pacific (UNESCAP, formerly the Economic Commission for Asia and the Far East or ECAFE) and non-regional developed countries.
Starting with 31 members at its establishment, by 2019 ADB had 69 members. As of 31 December 2020, Japan and the United States each hold the largest proportion of shares at 15.6%. China holds 6.5%, India 6.3%, and Australia 5.8%.