She completed her studies in 1899 and received a fellowship to undertake research for her Master of Arts degree in medieval history at Columbia University.

Throughout her tenure as dean of Barnard College, Gildersleeve worked to advance women's rights by championing their access to the professional school at Columbia and to its best professors.

In the two decades before World War II, this process of selective admissions reduced the percentage of Jewish students at Columbia to match the 20 percent at Barnard.

[7] In 1942, early in World War II, Gildersleeve was instrumental in founding the WAVES ("Women Accepted for Volunteer Emergency Service").

She was able to insert into the charter the following goals for people around the world: "higher standards of living, full employment, and conditions of economic and social progress and development."

She also persuaded the delegates to adopt the following aim for the United Nations: "universal respect for human rights and fundamental freedoms for all without distinction as to race, sex, language, or religion."

[11] Gildersleeve wrote that "after (her) retirement from the Deanship at Barnard, (she) devoted (her)self mainly to the Middle East",[12] describing herself as "struggling ardently against" the creation of and, later, the continued existence of the Jewish State.

"[14] Gildersleeve repeatedly testified before congressional committees and lobbied members of Congress and President Harry Truman to deny American political, military, and financial support to Israel.

She helped found and chaired the Committee for Justice and Peace in the Holy Land, which merged into the American Friends of the Middle East.

[15] According to the historian Robert Moats Miller of the University of North Carolina, the group was funded by the Central Intelligence Agency and ARAMCO.

In 1931, she raised the matter with Columbia President Butler, who "looked a little startled", but he agreed, saying "We should have women teachers with fuller lives and richer experience, not so many dried-up old maids".

[4] In 1915, in a speech to the Columbia Chapter of Phi Beta Kappa she challenged the commonly held belief that the education of women was a detriment to society, arguing that improved public health and the declining infant mortality made it unnecessary to breed so many children as once had been the case in order to have surviving progeny.

And in helping to draft the charter of the UN, Gildersleeve assured that the issues to which she had devoted her career on Morningside Heights would be addressed throughout the world in the decades that followed.

Later, she lived with the Barnard English professor, Elizabeth Reynard, and they both are buried at Saint Matthew's Episcopal Churchyard, Bedford, New York.

Gildersleeve imagined an organization built on the model of the American Association of Collegiate Alumnae and the British Federation of University Women.

To date, the fund has awarded more than 400 grants for a total project aid disbursement of more than US$1.8 million to women's groups in low-per-capita-income countries.

Priority is given to income generation and community development projects that enhance and exercise women's educational, vocational, and leadership skills.