Dr. Leonard is Research Assistant Professor of Epidemiology in the Department of Biostatistics, Epidemiology, and Informatics, Faculty of the Institute for Translational Medicine and Therapeutics, Core Faculty of the Center for Therapeutic Effectiveness Research, and Investigator and Executive Committee Member of the Center for Pharmacoepidemiology Research and Training—all at the Perelman School of Medicine at the University of Pennsylvania. He is Senior Fellow of Penn’s Leonard Davis Institute of Health Economics and Fellow of Penn’s Institute on Aging. Dr. Leonard is known nationally and internationally for his contributions in the field of pharmacoepidemiology and clinical pharmacology—including comparative safety of medical products in multimorbid populations, adaptation of pharmacoepidemiologic methods for studying drug interactions, co-development of methods for causal inference and health outcome of interest validation. Dr. Leonard serves as Applied Surveillance Core Co-Leader for FDA’s Sentinel Initiative―developing prospective surveillance plans and protocol-based assessments to facilitate the rapid identification and assessment of safety issues with medical products. He is Executive Editor of the British Journal of Clinical Pharmacology and Associate Editor of the journals Pharmacoepidemiology and Drug Safety and BMC Pharmacology Toxicology. In addition to his research and teaching, Dr. Leonard is Senior Manager of a clinical program to improve outpatient medication use within Penn Medicine.