The following three sections are devoted to three specialized populations—children and adolescents, the elderly, and adults with substance abuse problems—with each containing three chapters on the relevant epidemiological, treatment, and policy issues. These sections are uneven in quality and comprehensiveness. For example, the chapter on epidemiology of psychiatric disorders among the elderly is too detailed, and the reader becomes impatient. On the other hand, the treatment chapters in these three sections provide rather limited coverage; in addition, they have an extremely clinical orientation, not well balanced with a service perspective. The selection of these three populations results in the omission of relevant treatment, service, and policy issues related to adults with severe mental illness, such as those who are homeless, those who are in jails and prisons, and those who need psychiatric rehabilitation.