While a law student, she worked in the Office of the White House Counsel.

After law school, McMurray worked at Patton Boggs and then Kirkland & Ellis.

From 1991 to 1995, she was Republican Counsel to the United States Senate Committee on Environment and Public Works.

In early 2006, President of the United States George W. Bush nominated McMurray to be Assistant Secretary of State for Oceans and International Environmental and Scientific Affairs and, after Senate confirmation, she held this office from February 2006 until January 2009.

She is currently Senior Counsellor with The Prince of Wales' International Sustainability Unit.