In this book, leading internists and surgeons comprehensively and action-orientedly present the therapy of chronic inflammatory bowel diseases such as Crohn's disease and ulcerative colitis. They describe the specific aspects of treatment, but especially the interfaces of interdisciplinary collaboration that require close coordination between internists and surgeons. The primary medical therapy is contrasted with the surgical approach, which aims to preserve the bowel whenever possible. Diagnostics, special situations, extraintestinal manifestations, and therapy-associated complications are dedicated to their own chapters. The book is rounded off with discussions on pathogenesis and epidemiology, the peculiarities of inflammatory bowel diseases at different stages of life, as well as adjunct therapies.