Tanganyika was admitted to UN membership on 14 December 1961, and Zanzibar on 16 December 1963; following their union into what was eventually called Tanzania, the two regions retained a single membership. Tanzania is a member of ECA and all the non-regional specialized agencies. It is also a member of the African Development Bank, Commonwealth of Nations, ACP, G-77, WTO, and AU and is a signatory to the Law of the Sea.
On 1 December 1967, the heads of state of Kenya, Uganda, and Tanzania created the East African Community (EAC), with its headquarters at Arusha. The three countries maintained a common external tariff and corporations to run their airlines, railways, harbors, postal delivery, telecommunications, and other services. However, the EAC was dissolved in 1977. Tanzania is a member of the Southern Africa Development Community (SADC) and the Preferential Trade Area for East and Southern Africa. Along with Rwanda, Burundi, and Uganda, it belongs to the Kagera Basin Organization.