"Détente" is the name of the Cold War-era policy designed to reduce tension between the United States and the Soviet Union. The word "détente" means "a release from tension" in French.
After the tense nuclear standoff of the Cuban Missile Crisis in 1962, the leaders of the United States and the Soviet Union began to take steps to reduce the chance of catastrophe. Eventually, these steps led to the policy of détente. Though historians dispute when the policy began to take effect, many date it to the late 1960s with the signing of the Outer Space Treaty and the Nuclear Non-Proliferation Treaty. Further agreements followed including SALT I (1972) and the Helsinki Accords (1975). Détente grew weaker in the late 1970s, and effectively ended with the Soviet invasion of Afghanistan in 1979 and the subsequent U.S. boycott of the 1980 Moscow Olympics.