Pneumothorax is a common problem in both hospitalized and emergency room patients. Eight-four pneumothoraces in 79 patients were treated using a No. 9 French catheter. In 76 cases, the catheter was attached to a flutter valve, and in eight cases, suction was applied. The No. 9 French catheter provided definitive treatment in 73 (87 percent) of the pneumothoraces. Causes of catheter failure included kinking, malposition, inadvertent removal by patient, occlusion of the tube or valve by pleural fluid, and large air leak. No complication attributable to tube placement occurred. When the flutter valve was employed, the patient was able to ambulate allowing for potential outpatient therapy. The tube was found to be easy to use, safe, and efficacious in the treatment of pneumothoraces.