Dr. David L. Callender is President & CEO of Memorial Hermann Health System, one of the largest nonprofit health systems in Southeast Texas with more than 280 care delivery sites, including 17 hospitals across Greater Houston.

With a workforce of more than 35,000 employees and 6,400 affiliated physicians, Memorial Hermann is committed to delivering the highest standards of safe, evidence-based, quality care to provide a personalized experience for its two million annual patient encounters. For over 118 years, Memorial Hermann has remained steadfast in its mission to improve health in the Greater Houston community, contributing nearly $500 million annually through various community health programs.     

Since his appointment in 2019, Dr. Callender has spearheaded a multi-year strategy for Memorial Hermann aimed at enabling the entire health system to create more value for patients and populations; this includes delivering the greatest outcomes at an optimal cost, creating exceptional experiences for patients and a fulfilling work environment for its workforce, and improving health access in the communities Memorial Hermann serves.  

Beyond his role at Memorial Hermann, Dr. Callender is a tenured Professor of Otolaryngology at the University of Texas Medical Branch (UTMB Health). He serves on the Boards of the Texas Hospital Association, the Greater Houston Partnership, The United Way of Greater Houston, Good Reason Houston, and Longitude Health, a health care collaborative of which Memorial Hermann is a founding member. He also serves on the American Hospital Association’s Committee on Health Care Strategy and Innovation, the Texas Hospital Association’s Nominating Committee, the Greater Houston Partnership’s Health Care Advisory Committee, and is a member of the Healthcare Institute and University of Houston’s Board of Visitors.

Prior to joining Memorial Hermann, Dr. Callender served as President of UTMB Health for 12 years. Other previous roles include Associate Vice Chancellor and Chief Executive Officer for the UCLA Hospital System and Executive Vice President and Chief Operating Officer for The University of Texas MD Anderson Cancer Center.

Dr. Callender’s outstanding leadership has earned national acclaim, including four consecutive appearances on Modern Healthcare’s prestigious list of “The 100 Most Influential People in Healthcare” beginning in 2022. Dr. Callender has received several acknowledgements from Becker’s Hospital Review, including being named as one of the nation’s “Great Leaders in Healthcare” in 2024 and 2025, honored as one of their “CEO Influencers to Know” in 2024 and 2025, and named to their list of “Academic CEOs to Know” in 2025.

Dr. Callender earned his medical degree and completed his residency at Baylor College of Medicine. He also completed an oncology fellowship with The University of Texas MD Anderson Cancer Center and holds an MBA from the University of Houston.