Preoperative chemotherapy is a real challenge in the treatment of non-small cell lung cancer. From the first phase II studies, we have learned that response rates to preoperative chemotherapy were high, around 70% with approximately 10% of complete responses. Although toxicity seemed acceptable, increased morbidity and mortality were observed and have to be taken into account for the choice of the preoperative chemotherapy regimen. Two randomized trials were initially conducted in stage IIIA disease and showed highly positive survival results. However, only few patients had been included in both studies, and their statistical value has been considered as questionable. The French MIP91 study, whose results have been published in 2002, argues in favour of preoperative chemotherapy but could not demonstrate a clear-cut advantage. New studies are ongoing. In the search of effective and less toxic combinations, cisplatin-gemcitabine has a role to play. Several phase II studies of this regimen have been presented at the last meeting of the American Society of Clinical Oncology (ASCO) in the preoperative setting or in combination with radiotherapy, and confirmed its efficacy and good tolerability. Chemoradiation is important as part of the trimodality strategy including chemotherapy, radiotherapy, and surgery, which might become standard of care in the treatment of stage IIIa disease.