Recent progress in the molecular analysis of NSCLC tumors and lymph node status will likely translate into a clearer understanding of the variables and predictors of tumor recurrence. This understanding may lead to more appropriate therapeutic decisions both in the operating room and in the clinic. With these analyses at the molecular level, a more precise molecular classification is on the horizon which includes a molecular substaging. All of these aspects of NSCLC biology await testing or final analysis of prospective multi-institutional trials such as that set forth in CALGB 9761.