Barbash worked as an investigator for the New York State Department of Labor (1937–1939) and economist for the
National Labor Relations Board (1939–1940). In Washington, D.C., he worked for various unions and government agencies, including the US Office of Education (1940–1945), the War Production Board (1943–1945), and the Labor Department's
Bureau of Labor Statistics (1945–1949). He also worked as research and education director for the
Amalgamated Meat Cutters union (AMC) of Chicago (1948–1949). He then became staff director (1949–1953) of a subcommittee on labor-management relations on the US Senate's Labor Committee (currently called the
United States Senate Committee on Health, Education, Labor and Pensions). In 1953, Barbash joined the CIO's legal department as an economist and worked closely with
Arthur J. Goldberg, the CIO's general counsel, in negotiating the CIO to rejoin the AFL in 1955. Thereafter, Barbash served as director of research and education at the AFL–CIO. In 1957, Barbash became a professor of economics and industrial relations at the University of Wisconsin–Madison, where he taught for 24 years before retiring as the John P. Bascom Professor Emeritus of Economics and Industrial Relations in 1981. ==Personal life and death==