To examine the promise, concerns, and challenges related to neuroscience research using genetically modified nonhuman primates, the National Academies of Sciences, Engineering, and Medicine hosted a public workshop on October 4, 2018, bringing together an international group of experts and stakeholders representing academia, industry, laboratory animal management, disease-focused foundations, and federal agencies. The workshop was designed to explore the current state and future promise of research using genetically modified nonhuman primate models of disease to understand the complex functions of the brain that control behavior, movement, and cognition in both health and disease states. This publication summarizes the presentations and discussions from the workshop.