We undertook a randomized clinical trial to evaluate the efficacy of chest physiotherapy and intermittent positive-pressure breathing in the treatment of pneumonia. The diagnosis of pneumonia required a compatible clinical history and x-ray confirmation. A total of 54 patients were assigned to treatment and control groups and were similar in age, smoking history, underlying lung disease and prior antibiotic treatment. Antibiotic therapy, guided by Gram stain and sputum and blood cultures, was similar in both groups. Chest physiotherapy, consisting of postural drainage, percussion and vibration, was given concurrently with intermittent positive-pressure breathing with use of racemic epinephrine every four hours. There was no statistically significant difference in duration of fever, extent of radiographic clearing, duration of hospital stay and mortality between the control and treated groups. Chest physiotherapy and intermittent positive-pressure breathing do not hasten the resolution of pneumonia.