Mildred Fossier was born June 8, 1912, in New Orleans, Louisiana. Mildred graduated from Sacred Heart Academy and Newcomb College (1938), later obtaining a master's degree in social work from Tulane University in 1954. During World War II, she worked for the Federal Civil Service and was the first woman division head. After obtaining her masters, she became the director of social services for Milne Boys Home. In 1963 she became the first woman department head of the city. She was appointed the director of welfare under Mayor Vicor H. Shiro. In 1972, Mayor Moon Landrieu appointed her Director of the Department of Parks and Parkways. She retired in 1979, but remained active in civic service. Fossier worked alongside Congresswoman Lindy Boggs to establish the Bayou Sauvage National Wildlife Refuge. Fossier also served on the boards of several organizations, including the Girl Scouts of Southeast Louisiana, the Council on Aging, the League of Women Voters, and the Wetland Conservation Committee. She also served as a volunteer environmental consultant to the Mayor of New Orleans.