Singleton is an attorney with Husch Blackwell LLP and a leader in government affairs and regulatory law.  She has held several leadership positions in the U.S. House of Representatives and was appointed General Counsel to the U.S. Agency for International Development where she was the chief legal advisor to 72 U.S. missions around the world.   She represents companies and trade associations throughout a wide range of industries in public and regulatory matters. 

Ms. McAllister serves on the Board of Directors of Alliant Energy, Anterix, Vice Chair of the National Women’s History Museum, and Chart Industries.  Singleton was voted onto the Proxy Board of Securitas Critical Infrastructure Services, Inc. and also served on the Board of Directors for United Rentals.   Directors & Boards Magazine honored her as a Director to Watch 2016 and Savoy Magazine, Power 300: The Most Influential Black Corporate Directors.  Singleton is a member of the National Association of Corporate Directors Compensation Committee Chair Advisory Council and has been recognized by its Directors 100 List for 2019.