Objective: Thoracic surgeons are performing robotic resections for anterior mediastinal tumors; however, tumors located in the posterior and especially the inferior chest can be difficult to approach robotically. The objective of this study was to evaluate the efficacy of the robot for resection of these tumors. Methods: We performed a retrospective review of the evolution and outcomes of our surgical technique for inferior or posterior mediastinal pathology. Results: During a 30-month period, 153 patients underwent robotic surgery for pathology in the mediastinum, located in the inferior or posterior mediastinum in 75 of these patients. The most common indications for surgery were posterior mediastinal mass or lymph node in 41 patients, esophageal or bronchogenic cysts in 11 patients, esophageal leiomyoma in 7 patients, and diaphragmatic elevation in 7 patients. The median tumor size was 4.4 cm, and the median length of stay was 1 day. One patient was converted to thoracotomy, but no patients were converted for bleeding. Morbidity occurred in 9 patients (12%), major in 1 patient (a delayed esophageal leak after epiphrenic diverticulectomy). There was no mortality. Technical improvements included using robotic arm 3 posteriorly for retraction, side-docking, or coming over the back of the patient for tumors inferior to the inferior pulmonary vein and for diaphragmatic plication and using the lateral decubitus position for extraction of tumors larger than 3 cm via an access port over the tenth rib above the diaphragmatic fibers. Conclusions: The robot affords safe access using a completely portal approach for resection of and surgical intervention for inferior and posterior chest pathology and for anterior tumors. Specific techniques can be used to improve the operation. Copyright © 2012 Published by Elsevier Inc. on behalf of The American Association for Thoracic Surgery.