In spite of the time and endeavour spent upon the treatment of pulmonary tuberculosis, it is far from the truth to say that the results of treatment are generally satisfactory.This statement is underlined by the figures of Thompson (1942Thompson ( , 1943, who found that 42% of a group of 406 patients with a positive sputum in th-County of Durham were dead within 12 months of diagnosis, while only one patient in eight survived for 10 years. Cox (1936) and Bradbury (1946) give figures from the Lancashire County Council which showed somewhat similar results. Of 1,230 cases of pulmonary tuberculosis notified in 1930, 63.1% had died of their disease within five years, and of the 1,178 cases notified in 1940, 58.3% died in a similar period. When it is considered that 27.9% of the cases notified in 1930 and 33.6% of the cases notified in 1940 were still under treatment at the end of five years, the figures are discouraging indeed.Stocks and Lewis-Faning (1944) conclude that, in spite of a rapid fall in the number of notifications of disease in the period from 1923 to 1939, the average expectation of a patient eventually dying of his disease remained unchanged.It would not be fair to conclude from these figures that the prognosis of certain types of cases has not improved, and, in particular, the study of patients treated by thoracoplasty shows reason for optimism. Hurford (1941) published details concerning a group of 67 patients treated by thoracoplasty and a similar number who declined this treatment when it was offered. On follow-up for a minimum period of one year, 65% of operated cases were quiescent compared with 16% of the controls; only 18% of operated patients, but 45.5% of the controls, were dead. Sellors (1947) recorded sputum conversion in 84% of 633 patients treated by thoracoplasty between 1935 and 1946; 59.2% were fit for full work and 12.1 % were dead. Similar figures are given by other authors.Over a period of years certain views have been developed on the pathology and treatment of this disease which will be discussed, and as a development from these a more direct attack on the diseased area in the lung has been adopted which it is hoped may produce some improvement on these figures.