100 Most Influential People in Healthcare - 2022

When Callender was tapped to head the system in 2019, he had already made a name for himself as a healthcare executive known for expanding access to care and advancing cutting-edge research. As CEO, he runs the organization’s 17 hospitals and healthcare network with an eye toward the future of healthcare. For example, Children’s Memorial Hermann Hospital announced a partnership this year with a school-based telehealth company to provide services to children in Houston. Callender is a surgeon with expertise in head and neck cancers. Before joining Memorial Hermann, he was president of the University of Texas Medical Branch at Galveston; associate vice chancellor and CEO at UCLA Health; and executive vice president and chief operating officer at MD Anderson Cancer Center.