This article addresses new developments in neuroscience, and their implications for law. It explores, for example, the relationships between brain injury and violence, as well as the connections between mental disorders and criminal behaviors. It discusses a variety of issues surrounding brain fingerprinting, the use of brain scans for lie detection, and concerns about free will. It considers the possible uses for, and legal implications of, brain-imaging technology. And it also identifies six essential limits on the use of brain imaging in courtroom procedures.