Review of Pulmonary Physiology.

It is our great honor and pleasure to present this special issue of Seminars in Respiratory and Critical Care Medicine devoted to pulmonary physiology. In this modern day of cell and molecular biology, the basics of pulmonary physiology are often overlooked and misunderstood by students and practitioners alike. These physiologic principles remain central to understanding human disease and treating patients, and while there are many excellent textbooks and other sources that cover the basics of pulmonary physiology, our goal was to provide a definitive source of information on not just the basics but also the wonderful complexities of the respiratory system.