Hans-Dietrich Genscher (born 21 March 1927) is a German politician of the liberal Free Democratic Party (FDP). He served as Foreign Minister and Vice Chancellor of Germany from 1974 to 1982 and, after a two-week pause, from 1982 to 1992, making him Germany's longest serving Foreign Minister and Vice Chancellor. In 1991, he was Chairman of the Organization for Security and Co-operation in Europe (OSCE).