The microvascular surgical anastomosis remains one of the most technically sensitive aspects of free-tissue transfers. To facilitate these often time-consuming, difficult anastomoses, various anastomotic coupling systems have been introduced. The 3M microvascular anastomotic coupling device, a polyethylene ring-pin device, was found to be highly successful in numerous animal studies. It has been available for use in human subjects for the last 4 years, but clinical experience remains sparse. Our clinical experience with the 3M coupler is reported in 100 free-tissue transfers. The average anastomotic time was 4 minutes. Mean follow-up was 8.6 months, and flap survival was 100 percent. The overall success rate for 3M (MACD) coupler use in microvascular anastomoses is 98.4 percent (121 of 123). Nine abandoned anastomoses were converted to sutured anastomoses intraoperatively. The over-all failure rate for 3M coupler anastomoses is 1.6 percent (2 of 123). We conclude that the 3M device is best suited for minimally discrepant, soft, pliable venous microvascular anastomoses and is unsuitable for end-to-side anastomoses in clinical situations. When carefully and selectively employed by a trained microvascular surgeon, the 3M coupler can be a safe, fast, and reliable adjunct for free-tissue transfers.