The surgical treatment of advanced oral cavity cancer presents a difficult reconstructive challenge since tumor resection can result in "through and through" bone and soft tissue defects. Reconstruction is essential for an acceptable aesthetic outcome, as well as functional oromandibular rehabilitation. The advent of microvascular free tissue transfer now allows immediate reconstruction of these large composite resections, and offers significant advantages over more traditional techniques. Success rates approach 90%-95% at most large centers. In this article, we describe the challenging decisions faced by clinicians treating these patients, and discuss our reconstructive method of choice, the fibula osteomyocutaneous free flap.