This volume brings together, for the first time, inquiries into the size and proximity of social networks and emotion in social relationships to advance understanding of how emotion in significant social relationships influences health. The collection integrates knowledge from those with expertise in mapping the nature of emotional experience in human relations with those who are linking social ties to health outcomes, and those who explicate underlying neurobiological mechanisms. The book puts forth the idea that full explication of how emotion, social relationships, and health are woven together demands multidisciplinary inquiry and brings together leading experts from fields of affective science, clinical and social psychology, epidemiology, psychiatry, psychoneuroimmunology, psychoneuroendocrinology, and health to promote the above synthesis.