In The Foundations of Immunology and their Pertinence to Medicine, Peter Bretscher describes how the few foundational concepts of immunology came about. He traces Jenner’s development of safe vaccination against small pox in the 1700’s, and how it led to the recognition of infectious disease by Koch and Pasteur in the 1880’s, and to the discovery of the Principles of Vaccination. The formulation of the Clonal Selection Theory in the 1950’s still provides a foundation for contemporary analysis of the immune system. Peter describes the main, and sometimes conflicting concepts, proposed in the last 50 years as to how immune responses are regulated. He develops a unique framework, and employs this to justify some tested and some speculative strategies to prevent and treat clinical conditions in five areas of medicine: Infectious Diseases, Cancer, Autoimmunity, Allergies and Transplantation. This book provides a platform for discussing contemporary immunological issues accessible to the non-specialist, medical students and medical practitioners. The platform challenges some of todays most popular paradigms. Foundations is written in a clear and jargon-free style.