OBJECTIVE To estimate the benefit of Video-Assisted Thoracoscopy (VAT) in the staging of patients with lung cancer. METHODS Between October 1998 and January 2001 VAT was used in 250 patients with histologically proven lung cancer. They were staged by more conventional techniques including magnetic resonance imaging (MRI), bronchoscopy, and mediastinoscopy. RESULTS As a result of VAT 30 patients were upstaged and spared a thoracotomy receiving neo-adjuvant chemotherapy at that point. In 40 patients the procedure was converted into an open thoracotomy and a curative resection was performed during the same session. The remaining 180 patients were deemed inoperable and they received chemotherapy and radiation treatment. CONCLUSIONS VAT enhanced our bronchoscopic and medistinoscopic findings. It was especially useful in assessing the extent of invasion of various thoracic structures amenable to surgical removal "en block" with the tumor, and in differentiating simple contact of the tumor with an intrathoracic structure from tumor invasion. In addition, it allowed access and sampling of lymph nodes in spaces not easily accessible by mediastinoscopy.