A retrospective study was performed in 107 patients with pneumonia in a total of 2231 who were admitted in a Medicine ward, of an University Hospital in Lisbon during 1990. From the studied patients, 50 (46,7%) were females and 57 (53,3%) males. The mean age was 70,7 +/- 15,3 years, with a mean of 12.8 admission days. In the past history it was identified 43 (40%) patients with respiratory illness. In this, the chronic obstructive airways disease were the more prevalent disease in 22 (20.5%) patients. In the other chronic debilitating diseases, registered in 90 (84.1%), we reported in 58 (54.2%) patients among cardiovascular illness, hypertension (H) in 17 (15.8%) cases and H with diabetes mellitus II (DMII) in 14 (13.1%). The most common radiographic pattern was bronchopneumonia in 56 (52.3%) cases and in the respiratory functional study, the partial respiratory insufficiency occurred in 25 (23.4%) cases. In blood test at admission, it was found anaemia in 35 (32.7%) patients, leukocytosis in 72 (67.3%), elevated sedimentation rate in 70 (65.4%), renal dysfunction in 12 (11.2%) and hyperglycemia in 67 (62.6%). Concerning therapeutics, the ampicillin was the most used antimicrobial therapy in 50 (46.7%) cases and the oxygenotherapy was necessary in 45 (42%). Only 29 (27.1%) needed bronchodilators and 3 (2.8%) required mechanical ventilatory support. The evolution was good in 76 (71%) cases and 31 (29%) patients died. The authors conclude that the pneumonia is a frequent disease in the Internal Medicine Clinics, either as admission cause either as complication of other comorbid medical condition and has a high mortality rate. The most important factors for the prognosis were the age of patients and previous diseases. The aim of the authors is to enhance prevention infection in lower respiratory tract, principally in the weak constitutions patients and the prescription of the appropriate therapy according with the judgment presumption and if possible with the isolated microorganism. Identify with the retrospective study, important elements in the clinical process for interpretation of diagnosis and therapeutic attitude and to learn with the preceding experience for future orientation.