Present-day respiratory physiology stems largely from the explosion of ideas which took place during and after World War II. A number of the major players are still active, but the opportunity to prepare a personal history of this branch of medicine will soon be lost. In a sense then, this book offers an exceptional, even unique, opportunity. We are offered a first-hand chronicle of the advancements made in respiratory physiology in the course of this century by one of the principal figures in the field. The volume covers every aspect of the evolution of this important area of knowledge: morphology, gas exchange and blood flow, mechanics, control of ventillation, and comparative physiology. Some of the chapters are personal accounts of the development of respiratory physiology as observed by the author. It is hoped that what is lost in objectivity by this approach is more than made up by the captivating insights provided by the author into the process of scientific research and discovery.