Seemingly the most natural and necessary of pursuits, a good night's sleep eludes a remarkable number of people-up to 50 percent of the general population, according to studies, while 10 to 15 percent suffer from severe or chronic sleep disorders. Because the causes and nature of sleeplessness are so many and varied-and often as elusive as sleep itself-the diagnosis and treatment require a flexible, multifaceted approach-and this is precisely what David N. Neubauer lays out in Understanding Sleeplessness. Building on the "four perspectives" conceptualized by McHugh and Slavney in The Perspectives of Psychiatry, Neubauer offers a much-needed explanation of the diverse ways of understanding what insomnia is and what should be done about it. He begins by surveying what is currently known about the mechanisms of "normal sleep" and, in this light, describing the problems of defining, assessing, and measuring insomnia. Drawing examples from patients studied at the Johns Hopkins Sleep Disorders Center, Neubauer then applies each of the four perspectives-diseases, dimensions, behaviors, life stories-to the varied kinds and degrees of sleeplessness. Finally, calling on the full range of perspectives on insomnia, he outlines an integrated approach to evaluation and treatment. His work will be of great interest and value to those who study and treat sleeplessness and to those who wish to understand this widespread and vexing problem.