Hilda Phelps Hammond’s career in politics and civil service began when Hammond served as president of the Newcomb College senior class of 1909. Newcomb College was the women’s coordinate college of Tulane University, and in her role as class president, Hammond worked with fellow notable classmates Natalie Vivian Scott and Martha Gilmore Robinson to put Newcomb on an equal standing with Tulane.

During the First World War, Hammond volunteered as the chairperson of the Louisiana Woman’s Committee of the Council of National Defense. In the 1930s, disillusioned with the corruption and power of the Huey Long political machine, Hammond helped form and served as president of the Louisiana Women’s Committee, an organization dedicated to ending Long’s control of state politics. With Hammond at the lead, the committee used radio, print, and a national letter-writing campaign, corresponding with senators and members of the national media.

Hammond’s work with the Louisiana Women’s Committee paved the way for New Orleans women to enter the political sphere. Veterans of the committee went on to form and were active in the League of Women Voters and the Independent Women’s Organization.