Steinberg’s involvement in county government began in 1965 when she served as deputy county counsel following completion of her law degree at Stanford University. Geraldine Steinberg was appointed to the Board of Supervisors in December 1974, becoming the first woman since Louise Ayer in 1935 to serve on the Board. In 1976, Steinberg became the first woman elected to the board. After becoming District 5 Supervisor, she served on the General Plan Committee for two years, helping to pass a two-year moratorium against subdivisions of unincorporated land until the general plan could be completed. Utilizing her strong skills as a consensus builder, she was able to resolve opposing interests of developers and environmentalists into agreements on ways to preserve the valley’s hillsides. Demands on her personal time convinced Steinberg to leave political office in 1981, allowing her to return to work as an attorney and to spend more time with her family.