This paper reviews 80 years of cooperation among central banks. Diverse modes of collaboration are identified, ranging from simple exchange of relevant information to mutual financial support and coordination of monetary actions. Central bank cooperation got off to a rocky start in the 1930s, following the creation of the Bank for International Settlements in 1930, but it improved in the 1950s and especially in the 1960s. Most early cooperation was among European central banks, although need for a trans-Atlantic dimension was soon evident. By the end of the 20th century both the problems addressed and the participants were drawn from around the world. The alleged dangers of central bank cooperation are found to have been exaggerated.