Dr. Zimmerman was appointed Chief Medical Officer at Mercy Health Plan in January 2004. She brings over twelve years of experience in healthcare management. Most recently, Dr. Zimmerman has been with CIGNA Healthcare as Associate Medical Director/Acting Senior Medical Director, responsible for medical management initiatives, Pharmacy and Appeals. Prior to CIGNA, Dr. Zimmerman was with Health Partners of the Midwest, BJC and Group Health Plans. She is active on a number of Boards, including the Diabetes Coalition.

Dr. Zimmerman received her medical degree from University of Missouri-Columbia and is board certified, American Board of Internal Medicine.