This dissertation is a social and legal history of one of Iowa's most controversial sex discrimination cases. The study examines the 1979 civil rights complaint of Linda Eaton, Iowa City's first woman firefighter--a white, working-class, single mother who did not consider herself a feminist. Eaton made national news and became the focus of an intense local debate when she was threatened with dismissal for breastfeeding her baby at the fire station. The president of La Leche League spoke out on her behalf, while the local chapter of NOW established a legal defense fund and spearheaded a year-long campaign of support. Mining the personal documents of community members, and using oral history interviews, manuscript collections, and legal documents, this study elevates the importance of grassroots action by demonstrating that local women's sex discrimination complaints and lawsuits were central to the dramatic transformation of workplace policies that began across the U.S. during the 1970s. This study foregrounds the relationship of Eaton's case to Iowa City's vibrant 1970s feminist community, and to national politics. The controversy over Iowa's breastfeeding firefighter reflected and contributed to national struggles over the meaning of gender equality, particularly the complex debates about affirmative action and the Equal Rights Amendment. Because she drew support from both the feminists of NOW and the maternalists of LLL, Eaton's case highlights the problematic intersection of paid and domestic labor in women's lives, especially those of working-class women. Eaton's case critiques the masculine ideal worker standard and makes a bid for working conditions that accommodate women's biosocial role in reproductive labor. This project draws upon previously unavailable records to offer an historical account of the first career women firefighters in the U.S. that identifies the resistance these women met as they encountered the masculine culture of firefighting in the 1970s. It highlights both the strengths and weaknesses of using law to eliminate sex discrimination in the workplace by constructing a vivid portrait of women's slow and painful struggle for full economic citizenship.