A minority of lung cancers is potentially curable by surgery. Radiotherapy, chemotherapy or a combination of both play an important role in this type of cancer. There are three major ways of combining radiotherapy and chemotherapy: sequential combination, concurrent combination and alternating combination. This review of the literature focuses on combined modalities in inoperable, non-metastatic, non-small cell carcinoma of the lung. Widest experience has been accumulated with sequential combinations. None of the randomized trials demonstrated that this type of association is better than radiation alone. Concurrent combination schedules are more recent: phase II studies have shown a high response rate (50-80%) but modest median survival (9-12 months). Rapidly alternating programs are also recent. They are based on mathematical models and experimental studies showing a high degree of activity with this type of association. Clinical phase II studies are still limited; they demonstrate a high response rate (50-80%) but the impact on survival cannot be assessed at this time. Intermediate analysis of a collaborative study (Groupe d'Oncologie Thoracique Alpine) with 50 patients is encouraging: we obtained a high response rate with 80% overall response (32% complete and 48% partial responses) and median survival of 16 months. We will continue to investigate this type of combined modality.