She previously was the president and CEO of Martha's Table, a Washington D.C.–based non-profit that provides community-based solutions to poverty.

[5] Stonesifer spent two decades working at for-profit technology companies as a consultant to DreamWorks SKG and at Microsoft in various vice president positions.

The Interactive Media Division produced software titles including Encarta Encyclopedia, Magic School Bus Series and Microsoft Flight Simulator.

[4] She helped Bill and Melinda Gates found their foundation, growing it from its inception in 1997 to the world's largest philanthropy with 500 employees by the time she stepped down in 2008.

Stonesifer donates both time and resources to a number of other regional nonprofit organizations; serves on the boards of the National Museum of African American History and Culture, Center for Global Development, and the Broad Institute; is a member of the Circle of Allies and Champions for the National Council of Young Leaders, the advisory board for America Achieves, and the executive committee of RaiseDC; and is a Hope Street Group advisor.

In 2010, President Barack Obama appointed Stonesifer to serve as the Chair of the White House Council for Community Solutions.