 The impetus for the development of this unique collaboration between radiation oncology and thoracic surgery stems from the ongoing interest in improving the quality of care for patients with early stage NSCLC. The clinical research focus has been on determining the best treatment strategies for the significant number of patients with stage I lung cancer considered medically inoperable or high risk surgical candidates. In the aging population, pulmonary insufficiency, cardiac disease, as well as other comorbidities may preclude surgery or place patients at significant risk for complications after surgery. The evolution of stereotactic body radiotherapy SBRT in the medically inoperable population has resulted in relatively low local recurrence rates ranging from 3-20 with favorable overall and disease-free survival in inoperable patients with Stage I NSCLC. 