Barnhart, 50, is currently head of consulting firm JAB Associates. She has been working as a private consultant to state governments on welfare issues, and was named to the Social Security Advisory Board in 1997.
She served at the Department of Health and Human Services from 1990 to 1992 as assistant secretary for children and families and assistant secretary for family support, according to the Associated Press.
From 1986 to 1990 Barnhart served as the Republican staff director for the Senate Government Affairs Committee. Prior to that she was associate commissioner for family assistance at the Social Security Administration.
If confirmed by the Senate, she will manage a staff of 65,000 nationwide.