Stereotactic body radiotherapy for early stage lung cancer has yielded outstanding outcomes comparable to radical resection. The approach requires special technologic requirements and contouring expertise to be safely performed. For advanced lung cancers, standard fractionation with intensity modulate radiotherapy requires understanding of a different set of dose constraints and target objectives. This session will review both approaches. At the conclusion of this activity, the learner will be able to do the following: 1. Identify basic anatomy in the cases presented and understand normal tissue dose constraints and target dose objectives. 2. Describe the rationale for current contouring approaches for common clinical scenarios for lung SBRT and IMRT. 3. Define the ITV, CTV and PTV for lung cancer in SBRT and IMRT treatment.