Inter-American Treaty of Reciprocal Assistance

Rio Treaty

Inter-American Treaty of Reciprocal Assistance Traité interaméricain d'assistance réciproque Tratado Interamericano de Assistência Recíproca Tratado Interamericano de Asistencia Recíproca
Member states in green with Venezuela in light green.[a]
Signed	2 September 1947[1]
Location	Rio de Janeiro[1]
Effective	3 December 1948[1]
Condition	Ratification by two-thirds of the signatory states
Signatories	23[1]
Parties	17[1]
Depositary	Pan American Union
Languages	English, French, Portuguese, and Spanish

The Inter-American Treaty of Reciprocal Assistance (commonly known as the Rio Treaty, the Rio Pact, the Treaty of Reciprocal Assistance, or by the Spanish-language acronym TIAR from Tratado Interamericano de Asistencia Recíproca) is an intergovernmental collective security agreement signed in 1947 in Rio de Janeiro among many countries of the Americas.^[2][3]

The central principle contained in its articles is that an attack against one is to be considered an attack against them all;^[3] this was known as the "hemispheric defense" doctrine.^[4] Despite this, several members have breached the treaty on multiple occasions.

The treaty was initially created in 1947 and came into force in 1948, in accordance with Article 22 of the treaty. The Bahamas was the most recent country to sign and ratify it in 1982.^[1]

Cite error: There are <ref group=lower-alpha> tags or {{efn}} templates on this page, but the references will not show without a {{reflist|group=lower-alpha}} template or {{notelist}} template (see the help page).