In this “masterpiece... the preeminent historian of neuroscience” (Science) explores psychiatry’s frustrated efforts to understand mental disorders as medical disorders. Anne Harrington reveals how psychiatry’s waxing and waning theories have been shaped, not just by developments in the clinic and laboratory, but also by a surprising range of social factors. The “enthralling Mind Fixers” (Nature) recounts the past and present undertaking to understand the biological basis of mental illness—its potential and its limitations—in order to lay the groundwork for creating a better future, both for those who suffer and those whose job it is to care for them.