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1010 10th Street
Modesto, CA 95354
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Health Services Agency


Mary Ann Lilly

Managing Director

Mary Ann Lilly is the Managing Director of the Health Services Agency of Stanislaus County. The Health Services Agency is comprised of the Public Health department, an outpatient clinic system, and the Indigent Health Care Program that operates a coverage program for indigents. Mary Ann also serves as the Executive Director to the Community Health Center Board, which partially governs the primary care clinics of the County’s clinic system. Prior to becoming the Agency’s Director in 2006, Mary Ann served as the Associate Director of Health Coverage & Quality Services, responsible for the Managed Care/Risk Management department and the Indigent Health Care Program department, and other project management. She began working for the Health Services Agency in 1999.

Before joining the Agency, Mary Ann served as Vice President of Contract Management for the Cleveland Health Network, a division of the Cleveland Clinic in Cleveland Ohio, and as Sr. Director Provider Network Management for National Health Plans in Modesto, California.

Mary Ann serves on the Stanislaus County Children and Families Commission, the Emergency Medical Services Committee, the Valley Consortium for Medical Education Board, and is an active participant in the County Health Executives Association of California.

Mary Ann enjoys working to achieve efficient operations while at the same time serving residents of the community including those who need it most. Mary Ann received her BS from California Polytechnic State University, San Luis Obispo and her MBA from Regis University.

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