After failure of first-line chemotherapy for advanced non-small cell lung cancer, many patients remain candidates to receive further antitumor treatment. To guide clinical management of these patients and to suggest priorities for clinical research, an International Panel of Experts met in Naples (Italy) in April 2007. Results and evidence-based conclusions are presented in this article. Single-agent chemotherapy with docetaxel or pemetrexed is the recommended option for unselected patients with performance status 0 to 2 who are candidates for second-line chemotherapy for advanced non-small cell lung cancer. Docetaxel has demonstrated superiority compared with best supportive care. Pemetrexed has been shown to be noninferior to docetaxel, with a more favorable toxicity profile. Erlotinib is effective in pretreated patients, and can be given second-line in patients not suitable or intolerant to chemotherapy, and in all patients as third-line treatment after failure of second-line chemotherapy. Gefitinib failed to show superiority to placebo as second- or third-line treatment, but it has been shown to be noninferior to docetaxel. In selected patients such as lifetime nonsmokers or those of East-Asian ethnicity, erlotinib, or gefitinib (where licensed) may be considered as second-line treatment even if they are fit for chemotherapy. Best supportive care in addition to active treatment remains important for all patients, but may be the exclusive option for patients unsuitable for more aggressive therapy. Further research is mandatory, to find better treatments, and to identify clinical and molecular predictive markers of efficacy, both for chemotherapy and for novel biologic agents.