The American Association of University Women (AAUW), officially founded in 1881, is a non-profit organization that advances equity for women and girls through advocacy, education, and research. The organization has a nationwide network of 170,000 members and supporters, 1,000 local branches, and 800 college and university partners. Its headquarters are in Washington, D.C. AAUW's CEO is Gloria L. Blackwell.

In 1881, Emily Fairbanks Talbot, Marion Talbot and Ellen Swallow Richards invited 15 alumnae from 8 colleges to a meeting in Boston, Massachusetts. The purpose of this meeting was to create an organization of women college graduates that would assist women in finding greater opportunities to use their education, as well as promoting and assisting other women's college attendance. The Association of Collegiate Alumnae or ACA (AAUW's predecessor organization) was officially founded on January 14, 1882. The ACA also worked to improve standards of education for women so that men and women's higher education was more equal in scope and difficulty.

At the beginning of 1884, the ACA had been meeting only in Boston. However, as more women across the country became interested in its work, the Association saw that expansion into branches was necessary to carry on its work. Washington, D.C., was the first branch to be created in 1884, and New York, Pacific (San Francisco), Philadelphia, and Boston branches followed in 1886.

In 1885, the organization took on one of its first major projects: they essentially had to justify their right to exist. A common belief held at the time that a college education would harm a woman's health and result in infertility. This myth was supported by Harvard-educated Boston physician Dr. Edward H. Clarke. An ACA committee led by Annie Howes created a series of questions that were sent to 1,290 ACA members; 705 replies were received. After the results were tabulated, the data demonstrated that higher education did not harm women's health. The report, "Health Statistics of Female College Graduates", was published in 1885 in conjunction with the Massachusetts Bureau of Statistics of Labor. This first research report is one of many conducted by AAUW during its history.

In 1887, a fellowship program for women was established. Supporting the education of women through fellowships would continually remain a critical part of AAUW's mission.

Back in 1883, a similar group of college women had considered forming a Chicago, Illinois branch of the ACA; however, they had reconsidered and formed their own independent organization. They formed the Western Association of Collegiate Alumnae (WACA) with Jane M. Bancroft as its first president. WACA was broad in purpose and consisted of five committees: fine arts, outdoor occupations, domestic professions, press and journalism, and higher education of women in the West. In 1888, WACA awarded its first fellowship of $350 to Ida Street, a Vassar College graduate, to conduct research at the University of Michigan. In 1889, WACA merged with the ACA, further expanding the groups' capacity.

In 1919, the ACA participated in a larger effort led by a group of American women which ultimately raised $156,413 to purchase a gram of radium for Marie Curie for her experiments.

In 1921, the ACA merged with the Southern Association of College Women to create the AAUW, although local branches continued to be the backbone of AAUW. The policy of expansion greatly increased both the size and the impact of the Association, from a small, local organization to a nationwide network of college educated women, and by 1929, there were 31,647 members and 475 branches.