Objective: Traumatic diaphragmatic hernias are a rare complication of blunt abdominal trauma. Despite increased incidence of use of abdominal CT imaging in trauma patients which is both reasonably sensitive and specific for this unusual finding, delayed presentation is not uncommon, and may occur months to years after the initial injury. Repair of chronic traumatic diaphragmatic hernias which present long after the initial injury can be a challenge for surgeons due to chronic incarceration and intraabdominal and intrapleural adhesions. Multiple approaches for repairing these defects have been described, including laparotomy, thoracotomy, laparoscopy, and thoracoscopy. In this video, we present our technique for robotic-assisted laparoscopic repair of a chronic traumatic diaphragmatic hernia. Case Video Summary: A 54-year-old female was involved in a motor vehicle collision and presented to an outside hospital for evaluation of left upper quadrant pain, where she was diagnosed with rib fractures and ultimately discharged to home. One year later, her pain had still failed to resolve, leading her to a gastroenterologist who performed unremarkable upper endoscopy and then ordered a CT scan, which revealed a large defect in the lateral left hemidiaphragm with herniation of small bowel, colon, and mesenteric fat into the left pleural cavity. In the video, we demonstrate our robotic-assisted laparoscopic repair, with reduction of all abdominal contents from the pleural cavity, primary closure of the defect with interrupted pledgeted sutures, reinforcement with running barbed suture, and onlay with PTFE mesh. The patient did well post-operatively with follow up imaging demonstrating success of the repair.