Despite surgery, resectable NSCLC (stage I, II, and IIIA N2) has a quite poor prognosis: about 50% of patients will die during the first 2 years by metastatic disease and only 36% are alive at 5 years after diagnosis. Postoperative radiotherapy is not effective in case of complete resection (PORT meta-analysis). The role of perioperative chemotherapy is still questionnable. Cambridge meta-analysis has shown a little benefit of cisplatin based postoperative chemotherapy. Several randomised trials are completed like Alpi Trial or ANITA or still in progress. Results would be available in 2 or 3 years. Several phase II trials of preoperative chemotherapy have demonstrated that preoperative chemotherapy is feasible, with high response rate, very few progression (mainly metastatic progression without local progression) and no increase of mortality and morbidity. Two small phase III trials have demonstrated that preoperative chemotherapy can dramatically increase survival compared with surgery alone, in case of N2 disease. The MIP trial of Depierre has studied two or four cycles of MIP regimen in perioperative setting in stage IB, II or IIIA, compared to surgery alone (TRT in case of N2 disease). After 3 years of survey there is a trend in favor of MIP in case of stage IB and II (23% increase of 3 years survival) but not in case of N2. The toxicity of MIP is a possible explanation of such poor results in N2 patients despite a high response rate (64%). Some other trials are in progress in the world. Surgery is also questionnable in case of resectable N2 disease. Several trials comparing chemo radiotherapy to chemo (+/- radiotherapy)+surgery are in progress in U.S. and Europe.