In spite of the significant advances made in the conventional treatment modalities currently available for the treatment of lung cancer, this malignancy remains the most frequent cause of cancer death in North America. In recent years, therefore, much attention has been given to identify noncross-resistant modalities of treatment that could potentially be used as an adjunct in the therapy of lung cancer. Recently there has been increasing optimism that gene therapy may be utilized as an approach to develop these novel anti-cancer treatment modalities. The field of gene therapy is still in its infancy with no major successes being reported yet in the treatment of cancer patients. However the limited positive results that have been reported have demonstrated the possibilities of this approach. With regard to the treatment of cancer patients, there are four main strategies that have been devised. These include the introduction of suicide genes, the replacement of defective tumor-suppressor genes, the inactivation of oncogenes, and immunotherapy.