The purpose of this review was to evaluate the utility of the 20 MHz microvascular implantable Doppler probe for free-tissue transfer, both intra- and postoperatively. Over a 15-month period, the Doppler probe was used in a total of 260 anastomoses, including 118 arterial and 142 venous microanastamoses. In these 260 anastomoses, there were six false positive results and eight true positives, resulting in one flap loss. The free flap success rate was 99 percent, the re-exploration rate was 8 percent, and the salvage rate was 83 percent. The internal Doppler offers an easy and reliable way to monitor microvascular free-tissue transfer both intra- and postoperatively. This study demonstrates the continued increase in survival, as well as salvage, of free-tissue transfer.