The revolution in scientists' ability to identify and manipulate genes has spurred all sorts of ethical debates, but an equally profound revolution--in brain science--is attracting amazingly little attention. Progress in many areas of neuroscience promises not only to reveal how the brain works in general but to provide information about intentions, thoughts and feelings as well as the mental aberrations that plague so many. Sophisticated imaging tools are enabling scientists to see which parts of the brain are active at any given time and to observe the effects of drugs, fear or other stimuli. Because the structure and activities of the human brain influences mental health and behavior much more directly than genes do, it is very likely that advances in the ability to "read" the brain will be exploited as much as, or more than, knowledge of genetics for such purposes as screening job applicants, diagnosing and treating disease, determining who qualifies for disability benefits and, ultimately, enhancing the brain. It is hard to argue that anything is fundamentally wrong with trying to detect and ameliorate brain disease. But those efforts nonetheless raise serious issues similar to those arising from the ability to perform genetic testing and therapy.