9to5 (also known as 9to5, National Association of Working Women) is a non-profit 501(c)(3) organization founded in 1973 in Boston during the rise of the Women’s Movement by Karen Nussbaum (now head of AFL-CIO affiliate Working America) and Ellen Cassedy. The organization focuses its efforts on advocacy towards voters as well as petitioning politicians in support of the labor-union agenda of employer mandates, with a special focus on mandates that affect women.
In the early 1970s, left-wing activist Karen Nussbaum founded 9to5 to advocate for the labor agenda to and on behalf of women. In 1975, the organization joined with the Service Employees International Union (SEIU), forming SEIU Local 925 and later the SEIU District 925. Nussbaum served as executive director of 9to5 and president of the 925 unions until 1993, when she accepted the position of director of the Women’s Bureau of the Department of Labor under President Bill Clinton.
The organization allegedly inspired the 1980 Jane Fonda film “9to5” and the song written for the movie. 
Currently, 9to5 is a membership organization of working women. It has expanded from its initial Boston focus and membership into a national organization. It currently has chapters in just five cities: Atlanta, Denver, Los Angeles, Milwaukee, and San Jose; however, the majority of its membership is contained in its “National Action Network,” which claims members and smaller local chapters in every state. 
9to5 receives the majority of its funding from contributions, though a small fraction (around 1%) derives from its offered programming and services.  Some major national donors, as listed on their website , include:
Caring Across Generations
Center for Law and Social Policy (CLASP)
Institute for Women’s Policy Research
Leadership Conference on Civil and Human Rights
National Council for Research on Women
National Domestic Workers Alliance
National Gay & Lesbian Task Force
SAVE for All
Too Small to Fail
Women for Economic Justice
Work Family Strategy Council
Karen Nussbaum, who co-founded the organization, had been involved in political activism since college. She joined an organization called the Black Panther Support Committee in the late 1960s, participated in the anti-Vietnam War movement and rallies, and participated in a pro-Fidel Castro “Venceremos Brigade” initiative in 1970, which transported hundreds of young Americans to Cuba to interact with Communist revolutionaries. In a 2003 interview, Nussbaum described her visit to Cuba in 1970 as “thrilling,” describing it as “a society that was combating racism, that had provided free health and educational care to every person in society, that had reduced income inequality more dramatically than any place else on earth.”
Nussbaum then moved to Boston, continuing her work with the antiwar movement and working as a clerical worker at Harvard. During this time, she, along with some friends, founded 9to5 as an organization of female clerical workers in the Boston area. Nussbaum served as director until 1993, when she left to serve as director of the Women’s Bureau in the Department of Labor during the Clinton Administration’s first term. She is now executive director of Working America, an affiliate of the AFL-CIO focusing on recruiting non-unionized workers, which she co-founded in 2003.
Ellen Cassedy co-founded 9to5 with Nussbaum. She co-wrote a book with Nussbaum on labor issues titled 9to5: The Working Woman’s Guide to Office Survival. 
Helen Kim Ho has served as national executive director since 2017. She is a former civil rights attorney and founder and former executive director of the liberal group Asian Americans Advancing Justice-Atlanta.