The iliac crest osseocutaneous free flap, based on the deep circumflex iliac artery and vein, was a landmark contribution to head and neck reconstruction. Two major problems associated with this flap are the lack of flexibility in placement of the skin paddle with relation to the bone graft, and the excessive thickness of the skin paddle when used in the oral cavity. The scapular osseocutaneous flap has achieved recent popularity for mandibular reconstruction based, in part, on its thin skin paddle that is easily positioned in three dimensions with relation to the bone graft. However, the segment of bone that can be harvested from the iliac crest is superior to that of the lateral border of the scapula because of its increased length, thickness, and natural contour. In 1984 the internal oblique free muscle flap based on the ascending branch of the deep circumflex iliac artery was described for use in reconstruction of the extremities only. The authors introduce the application of the internal oblique-iliac crest osseomyocutaneous free flap for mandibular reconstruction. The mobility of the internal oblique muscle with relation to the iliac bone graft has permitted its use for inner mucosal defects or outer cutaneous defects when covered with a skin graft. Following denervation atrophy, the muscle component becomes a thin, pliable piece of tissue that easily conforms to three-dimensional defects of the head and neck. This increased flexibility, the established benefits of the iliac bone, and the ease of intraoperative positioning for a two-team approach make this composite flap an outstanding tool for mandibular reconstruction. Two representative cases and a detailed description of flap harvesting, insetting, and donor-site closure are presented.