Background. This multicenter prospective trial was designed to assess the safety and efficacy of using a robotically-assisted microsurgical system to create endoscopic coronary anastomoses. Methods. Thirty-two patients scheduled for elective primary coronary surgery underwent endoscopic anastomosis of the left internal thoracic artery (LITA) to the left anterior descending (LAD) artery. Three thoracic ports (two for instruments and one for a camera) were placed, and a robotic system was used to perform the LITA-LAD graft. Conventional techniques were used to perform the other grafts. Thirty-one patients underwent median sternotomy and 1 patient underwent a limited anterior thoracotomy. Results. Graft flow was measured in the operating room and averaged 37±19 mL/min. Mean anastomosis time was 24±9 minutes. There were three intraoperative revisions (9%). Two were for inadequate flow and one for an inadvertent injury. Each of these grafts was successfully revised by hand. There were no technical failures of the robotic system. Average postoperative length of stay was 5.5±2.7 days. There were three reoperations for bleeding, but none of these were related to the LAD anastomosis. Two months following the operation, selective angiography revealed a graft patency of 93%. The patients have been followed for 16±4 months. Conclusions. This initial prospective multicenter trial documents the feasibility of robotically-assisted coronary bypass grafting. Further trials are warranted to establish the safety and efficacy of this new technology.