This chapter focuses on the early developments in the Conference on Security and Cooperation in Europe (CSCE). During a period of relative détente in the Cold War, the CSCE negotiated between 1973 and 1975 the Helsinki Final Act among 35 states of Europe and North America, including all member states of the NATO and Warsaw Pact alliances and most neutral and non-aligned European states. In the military domain, these negotiations produced agreements on “confidence- and security- building measures” intended to reduce the likelihood of war in Europe. Equally important over the long term were agreements on the “human dimension of security,” including institutionalizing basic principles of human rights throughout the region. Although these principles were not fully implemented in the immediate aftermath, CSCE follow-on conferences in Belgrade, Madrid, and Vienna over the ensuing 15 years strengthened these provisions, eventually undermining authoritarian regimes in the Warsaw Pact states and contributing significantly to the end of the Cold War in 1989.