In spite of recent improvement of the medical and surgical treatments, there are many significant problems in the management of thoracic empyema. This is a clinical analysis of 49 cases of thoracic empyema who underwent lung decortication for a period of 6 years and 5 months extending from May, 1972 to Aug. 1975. The following results were obtained: Male to female ratio was 2. S to 1. The age ranged between Sand 69, bnt was mostly 2r.d and 5th decade. The underlying diseases were pulmonary tuberculosis (30 cases, 61. 1 SO, , ), posttraumatic hemothorax (7 cases, 14.396). pneumonia (6 cases, 12.2%), lung abscess (2 cases, 4.2%), paragonimiasis (2 cases, 4.2%). spontaneous pneumothorax (1 case, 2.1%), and unknown origin (1 case, 2.1%). In 13 cases (26.5%), positive bacterial growth on culture was reported. There were single infection in 11 cases and mixed infection in 2 cases. The organisms grown were Staphylococcus, alpha-hemolytIc Streptococcus, Alkaligenes fecalis, Escherichia coli, Pseudomonas, SerratIa, Enterobacter agglomerans, and Enterococcus in order of frequency. Staphylococcus, Streptococcus, and Serratia were sensitive to several different kinds of antibiotics. But Pseudomonas, Escherichia co:i, and Enterococcus were sensitive to only one or two antibiotics. Leukocytosis was observed In acute empyema, but not in chronic empyema. Hemoglobin and hematocrit were all within normal limits. Preoperative liver function tests were within normal limits in most of the cases. In 49 cases, lung decortication alone was performed in 40 cases (S1. 696), and for the remaining 9 cases (1S. 4%), additional surgical procedures were necessary, i. e., lobectomy (6cases). partial thoracoplasty (2 cases), and lobectomy & partial thoracoplasty (1 cases). The results of lung decortication in thoracic empyema were goed. 38 cases (77.5%) healed with no complication, and 10 cases (20.4%) were complicated by bleeding, wownd infection, pleural infection, chondritis, and psychosis. These complications resolved ultimately leaving no sequelae. One death was recorded (2.1%), and the causes of death were postoperative pleural infection, sepsis and hepatic insufficiency.