Closed tube thoracostomy is a standard procedure for the evacuation of air, blood, or other materials from the pleural space. This paper describes a modification of the Seldinger technique that facilitates chest tube insertion. Either a Nelaton or Thieman catheter is threaded into the side drainage hole and out the tip of a standard Argyle-type chest tube. After using the clamp to insert the catheter into the pleural space through a previously dissected tract, the catheter serves as a guide over which the chest tube is inserted. The technique is simple to use, effective, and safe. It employs standard, inexpensive materials to insert chest tubes in such a way as to minimize the potential traumatic complications inherent in other techniques.