CHEMOTHERAPY OF PRIMARY LUNG CANCER has benefited considerably from the experience gained in the combined use of chemotherapy for other malignancies. Yet the results obtained so far remain unsatisfactory. Small cell cancer is one of the human tumors which is very sensitive to the cell-killing effect of antitumor agents. Improved combined treatment schedules, including a chemotherapy—radiotherapy approach, can probably improve more consistently the survival of small cell tumor patients. For non-small cell types, the first priority in further therapeutic research should be placed on the development and clinical screening of new potentially active agents rather than on combinations of limited value.