Barrett A Toan

Barrett A. Toan was elected a director of Express Scripts in October 1990 and served as Chairman of the Board from November 2000 until May 2006. Mr. Toan was Express Scripts' Chief Executive Officer from March 1992 until his retirement in March 2005. Mr. Toan was an executive employee of Express Scripts from May 1989 until his retirement and served as President of Express Scripts from October 1990 to April 2002. Mr. Toan is also a director of Sigma-Aldrich Corporation, a specialty chemical company, and Genworth Financial, Inc., an insurance and financial services company.