The reported success rate of microvascular free flap reconstruction ranges between 95% and 97%. However when complications occur, they must be identified early and managed efficiently because there is a narrow window of opportunity to salvage potential flap failure. While technical advances in instrumentation and magnification have improved overall success rates, the rare complication may prove devastating for the patient, his/her hospital stay, and the optimum rehabilitation. Complications of microvascular free tissue transfer may occur at the recipient site or at the donor site. Complications occurring at the recipient site are largely a result of vessel thrombosis while complications occurring at the donor site may result from many causes, ranging from infection to those related to the harvesting of the flap. Irrespective of the site of the complication, it is essential that complications be recognized and addressed early in their course to prevent or minimize devastating consequences.