Deputy Director of the Division of Therapeutics and Medical Consequences of the National Institute on Drug Abuse of the United States. He is PhD in Medicine and Surgery with a specialization in Psychiatry from the University of Antioquia (Colombia). He obtained a Fulbright scholarship and a Master's degree in Public Health from Johns Hopkins University. He obtained a postdoctoral fellowship in the Intramural Research Program of the National Institute on Drug Abuse. He directs an extensive research program supporting the development of pharmacological and non-pharmacological treatments for substance use disorders. He has published extensively in the areas of etiology, prevention, treatment, and medical consequences of substance abuse.