This comprehensive, cross-disciplinary encyclopedia explores the developmental nature of social interactions and is designed for a broad range of readers in college, institutional, and public library settings. The lifespan perspective illuminates how relationships change throughout the course of human development from family interactions and friendships to dating and work relationships. In the process a diversity of topics are explored, such as aging experiences, divorce, family violence, gender roles, grandparenthood, HIV/AIDS and other sexually transmitted diseases, marriage and alternative lifestyles, parenthood, and sibling relations. A variety of perspectives are provided, including psychological, sociological, family studies, historical, anthropological, and religious views. The reader is also exposed to how lifespan relationships are shaped by international, racial, ethnic, and class differences.Over 500 easy-to-read entries analyze terms, concepts, themes, theories, and policies, as well as current, historical, and multicultural perspectives, and provide over 1,500 sources for further study. An appendix listing over 100 professional journals of note and a selected bibliography of the latest publications of importance to the topic overall further enrich this volume designed for students, teachers, practitioners, and general readers in all the social sciences.