After giving an outline of pneumogenic respiratory insufficiency, signally that deriving from chronic obstructive bronchopulmonary disease, the Authors describe the intensive care of respiratory insufficiency, first from the anesthesiologist's point of view and then in a broader medical sense. In regard to the latter, the Authors emphasize the importance of material equipment and staff training and teamwork; they also list a number of possible iatrogenic disorders in intensive care. Next they discuss medical aids and more specifically the machinery designed to assist respiration, such as pulmonary ventilators and the "iron lung", as implements that can be used to advantage in medical wards. Then they describe the elements to be used for a correct assessmnet of the severity of respiratory insufficiency, under the following subheadings:--state of coma, if present;--state of acid-base balance, oxemia, and water and electrolyte balance;--circulatory compensation or failure;--need for correcting bronchial obstruction. Through several representative examples concerning the medical correction of alterations of CO2, pH, electrolyte composition, and water and blood volumes, they describe the therapeutic measures to be undertaken particularly as regards the metabolic sequels (alkalosis or acidosis) that may occur in the course of treatment. Coming next to intensive care utilizing mechanical devices, they stress the importance of monitoring the parameters of humoral balance during (and even more so, after) said treatment, in view of avoiding the emergence of iatrogenic disturbances such as the reventilation syndrome and the syndrome of post-hypercapnic metabolic alkalosis.