Dr. Marion Mass graduated from Penn State University, Duke University School of Medicine and completed her pediatric training at Northwestern Children's Memorial Hospital.

She has lived in Greece and worked on a Native American reservation in Montana. She has practiced as a pediatrician in the Philadelphia region for over 20 years.

With the healthcare system declining, she began getting involved in reform efforts. She started her own physician advocacy organization, the Practicing Physicians of America with Dr. Wes Fisher, MD of Chicago in 2017.

Since that time she has had multiple speaking engagements, twice at the Library of Congress, and has published numerous articles in the Wall Street Journal, the Philadelphia Inquirer, the Hill, the Washington Examiner, the Washington Times and multiple articles in the Bucks County Courier Times where she is a community volunteer member of the editorial board.

She is on the board of the Bucks County Health Improvement Partnership, an organization that strives to fill unmet needs in her hometown of Bucks County where she lives with her husband, Steve, a surgeon, and their three children, 15, 18 and 20.