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Mark Diel

Chief Executive Officer

As CEO of NAHAA and CCHI, Mark is responsible for the strategic and day-to-day management of NAHAA and its staff. Prior to leading NAHAA and CCHI, he spent 9 years as Executive Director and CEO of Children’s Health Initiative Napa County where he developed the first nonprofit insurance brokerage firm in California serving individuals and families. He built a county-wide collaborative of 42 agencies and guided Napa County into a leadership role at the state level, working to provide affordable health insurance to everyone in California, regardless of race, ethnicity, or family income. Prior to his work in Napa County, he managed public health programs in Yolo County, including the Women, Infants, and Children Program. He also developed mobile medical, dental, and optometric clinics based in schools and community centers, and a health promotora program in Los Angeles. Mark holds a Bachelor’s degree from the California Polytechnic State University, San Luis Obispo, and Master of Public Health degree from the University of Hawaii.

Heather Bates


Heather most recently comes to NAHAA from the national nonprofit, Families USA, where she served as the Director of Community Engagement and helped develop the enrollment assister network. She is a founding leader of NAHAA and she recently relocated to California to build NAHAA's infrastructure from their headquarters in Sacramento. Heather has over 20 years of experience managing health policy related programming, staff and volunteers in order to meet the needs of consumers enrolling in Medicaid, Medicare, and most recently the Affordable Care Act (ACA). Prior to working for Families USA she worked for Enroll America/Get Covered America to launch state-based awareness and enrollment campaigns in several states across the country in order to establish outreach and enrollment best practices under the ACA. Prior to the implementation of the ACA, Heather worked for the national nonprofit, the Medicare Rights Center where she served as Vice President of Client Services. In this role Heather helped to restructure the organization, develop new programming, and expanded their national training and technical assistance programming to nonprofits enrolling Medicare beneficiaries into public benefits such as SNAP and LiHEAP, Medicare Savings Programs, Extra Help and Medicare Part D prescription drug plans. She has a Master’s degree in Social Work from the City University of New York’s Hunter College and her undergraduate degree from the Ohio University in Athens, Ohio. Heather grew up in Ohio and studied theater while attending the School for Creative and Performing Arts in Cincinnati. She loves to talk about the arts, the Midwest, the beauty of the coasts, and learn about all of the people and places in-between.

Katie Heidorn

Director of Development

As NAHAA's Development Director, Katie leads future development strategy and creates new and innovative opportunities for members. Katie previously served in California Governor Jerry Brown's Administration as Deputy Secretary, Special Programs, and as Assistant Secretary, Program and Fiscal Affairs, at the California Health and Human Services Agency (CHHS) from 2012 – 2016. Prior to her time at CHHS, Katie was Principal and Associate Consultant to the Senate Appropriations Committee from 2008 to 2011, was an Associate at the Dewey Square Group from 2007 to 2008, and served as a California Senate Fellow in then-Senator Tom Torlakson’s office from 2006 to 2007. Katie holds a bachelor’s of arts and sciences in Biochemistry and Molecular Biology and Comparative Literature from the University of California, Davis, and a master’s in public administration from the University of Southern California.

Liz Hagan

Associate Director of Policy

Elizabeth Hagan is Associate Director of Policy for NAHAA. In this position, she advocates for policies that help enrollment assisters and the consumers they serve. She also works with state and local partners to identify and elevate promising outreach and enrollment practices taking place across the country. Previously, Ms. Hagan was Associate Director of Coverage Initiatives at the nonprofit nonpartisan organization, Families USA, where she also focused on policies to foster successful enrollment. Prior to joining Families USA, Ms. Hagan was a Policy Analyst with Enroll America's Best Practices Institute. Ms. Hagan is based out of Washington DC and holds an MPA from George Washington University and a BA from Ohio State University.