How do brains make decisions? In this seminar, Dr. Anne Churchland tells us why understanding decision-making is important, and outlines common approaches to study decision-making in the lab using a variety of mammals. She describes findings that suggest accurate decision-making results from a combination of visual and auditory stimuli in both humans and rats, and tells of the discovery of an explore-exploit tradeoff that allows rats to respond optimally to changing environments. Dr. Churchland then outlines the major methods for tracking neural activity in the brain and shows how they have been used to determine that many brain areas are active during decision-making. She ends her talk with an overview of new directions in the field.