A lucid, accessible explanation of what recent research on the brain has revealed about the nature and origins of emotion. LeDoux, a researcher at New York University's Center for Neural Science, has been studying the neurological basis of emotions since the 1970s. He views emotions as biological functions of the nervous system and believes that studying how emotions are represented in the brain can lead to knowledge not possible through psychological experimentation alone. He opens by recounting the work previously done by cognitive scientists, pointing out its shortcomings with regard to emotional process. Contrary to earlier theorists, he asserts that ``there is no such thing as the `emotion' faculty and there is no single brain system dedicated to this phantom function.'' Rather, there are numerous systems, each having evolved for different functional purposes (from defense to procreation) and giving rise to different kinds of emotions. Noting that each must be studied individually, the author has concentrated on the basic emotion of fear and, through the study of fear conditioning in rats, has mapped out in detail the brain mechanisms that underlie fear reactions. To those skeptical about the relevance of such research for human beings, LeDoux argues persuasively that these basic brain mechanisms are essentially the same across species. Especially interesting are his explanations of the different kinds of memory and his discussions of anxiety disorders as functional disorders of the brain's fear system. LeDoux nearly always succeeds in translating the technospeak of neuroscience into ordinary English, but just in case, in the trickier sections he has provided line drawings that help the general reader follow along with relative ease. After reading this instructive and engaging book, those whose neurological vocabulary stopped with ``gray matter'' will find themselves conversing confidently about the amygdala, the hippocampus, and the cerebral cortex.