Psychoneuroimmunology is the study of interactions among behavioral, neural and endocrine, and immunologic processes of adaptation. These two volumes provide a clearly written, extensively referenced summary of some of the behavioral, neural and endocrine regulators of immune responses and immunologically mediated disease processes and of the behavioral and neuroendocrine effects of immune system activity. Several chapters expand upon topics reviewed in earlier editions of this series; most chapters cover active areas of research that have not previously been reviewed. As illustrated in this fourth edition, interdisciplinary research continues to provide evidence that the brain and immune system represent a single, integrated system of defense.