From 1983 to 1995 Owen Bieber was president of the United Automobile, Aerospace and Agricultural Implement Workers of America, the third-largest labor union in the United States. At age nineteen, Bieber was elected as an officer of his plant's union, United Automobile Workers (UAW) Local 687. By 1955 he was elected to the local bargaining committee and was involved in talks on local plant issues. In 1956 he was elected president of the local chapter. Bieber, a devoted Democrat, also worked on behalf of Senator John Kennedy's (1917–1963) campaign for the U.S. presidency in 1960. In 1972 he was appointed director of the region, a position he held until 1980, when he was elected a vice president of the UAW and moved to the union's Detroit headquarters. Bieber served as director of the UAW's General Motors (GM) department, the union's largest department with more than four hundred thousand members. In 1995 Stephen Yokich, head of the UAW's GM department and longtime rival of Bieber's, took over the job after Bieber reached the retirement age of sixty-five.