During the last 20 years two groups of investigators have concerned themselves with the problem of acid-base regulation at various body temperatures. Each group, in professional isolation, pursued a separate path. Surgeons and anesthe tists developed techniques and tools for hypothermic cardio-pulmonary by-pass operations and based their rationale for acid-base management on in vitro models of blood behavior. Physiologists and biochemists, on the other hand, endeavored to understand acid-base regulation in living organisms naturally subjected to changes in body temperature. Only in the last...