In this presentation, Dr. McLoud discusses the major types of non-small cell carcinoma (NSCLC) where staging is so important in the decision regarding surgery. As a radiologist our charge is what constitutes disease, in particular unresectable disease. Improved accuracy of staging decreases both the unnecessary thoracotomies and the number of mediastinoscopies. She illustrates her lecture with numerous examples and concludes with a summary of the changes proposed for the 7th Edition of the TNM Classification.