This article examines the international history of the early Brezhnev era, 1964–72, when the Soviet Union simultaneously became more politically stable and socially stagnant. Evidence from a variety of sources indicates that, contrary to the presumptions of many observers, Brezhnev had a serious programme (‘developed socialism’) for revitalising the Soviet system. This programme included a number of international and domestic measures to improve Soviet technology and consumer economy within a strictly managed political framework of authority. Improved relations with the United States and Western Europe (‘détente’) were crucial to this programme. Continued Cold War competition gave ‘developed socialism’ a necessary source of legitimacy. Brezhnev succeeded in selling this programme to other Cold War leaders, but he confronted debilitating resistance at home. Rising domestic expectations within the Soviet empire, the maturation of the post-Stalin generation of citizens, and pervasive social unrest exposed the hypocrisy and shallowness of ‘developed socialism’. Although Brezhnev's programme sought to give the Soviet system a new start, by the late 1960s it contributed to a deepening rot.