A survey of the various types of interpersonal relationships. It reviews the multiplicity of research approaches and results on interpersonal relationships and how they change over the life span. It also elaborates on the characteristics of the different types of relationships.

Introduction Ann Elisabeth Auhagen and Maria von Salisch; Part I. Fundamentals: 1. Towards a science of relationships Robert Hinde; 2. The development of different social relationships among children Lothar Krappmann; 3. Child-child relationships: symmetry and asymmetry among peers, friends and siblings Maria von Salisch; Part II. Family Relationships: 4. Parent-child relationships: childhood and adolescence Kurt Kreppner; 5. Relationships between adult children and their parents Yvonne Schutze; 6. Relationships between adult siblings; 7. Relationships within the extended family and different types of families Peter Kaiser; Part III. Romantic Relationships: 8. Heterosexual romantic relationships: beginning, maintenance and dissolution Hans Werner Bierhoff; 9. Lesbian and homosexual romantic relationships Pepper Schwartz; Part IV. Relationships between Non-Relatives in Private Life: 10. Adults' friendships Ann Elisabeth Auhagen; 11. Relationships between neighbors and between acquaintances Christian Melbeck; Part V. Professional Relationships: 12. Relationships among colleagues Oswald Neuberger; 13. Professional role relationships Anne Gaska and Dieter Frey; Epilogue; 14. Selected remarks about relationship research Gerold Mikula.