Ida Klaus (1905-1999) was born in Brownsville, Brooklyn and organized her first union as a teenager while working at a hotel in Saratoga Springs, NY. Klaus graduated from Hunter College and the Teachers Institute of the Jewish Theological Seminary of America. She was initially denied entry to the Columbia University Law School because she was a woman, but later became part of the first class accepting women and graduated in 1931. Klaus went on to work first for the National Labor Relations Board and then the New York City Department of Labor. Klaus was the author of the "Little Wagner Act," which gave city employees the right to organize and bargain collectively, and also wrote the first detailed code of labor relations for city employees. In the early 1960s Klaus negotiated the first citywide teachers' contract in the country on behalf of the New York City Board of Education.

Klaus was involved in notable negotiations between unions that represent teachers, steelworkers, postal workers, railroad workers and local and federal government. She served on the Arbitration Law committee for the American Arbitration Association, International Labor Relations Law committee of the American Bar Association, Columbia Law School Board of Visitors.