We performed 25 fresh cadaver dissections to describe the anatomy of the superficial and deep circumflex iliac artery and the superficial inferior epigastric artery to determine how they could least to used as donor vessels for the free transfer of groin flaps and living iliac bone. With injection of ink the capillary region of these vessels was stained in (iliac crest) bone, the internal oblique muscle and skin of the groin and thigh. The superficial and deep circumflex iliac artery were shown to be the main supply vessels of the groin and thigh and could be found in 96%-100% of cases. The venous drainage of this region followed from a superficial system (superficial circumflex iliac veins) and a deep venous system (Vv. comitantes accompanying arterial branches). Both venous systems could always be found. The superficial circumflex iliac artery was shown to only supply the skin and was the main donor vessel to the skin and soft tissue transplants. The deep circumflex iliac artery supplied the pelvic bone, the internal oblique muscle and a small constant area of skin above the iliac crest. Bone, muscle and bone, muscle and skin transplants could be obtained with this donor vessel, with enlargement of the skin area possible by combining two arterial branches combined in one transplant. With an average vessel diameter of 1.5 mm (superficial circumflex iliac artery) and 3 mm (deep circumflex iliac artery) both vessels could be used satisfactorily for microvascular transplantation. Different tissues including muscle, bone and skin could be obtained in adequate amounts to replace composite defects in the upper aerodigestive tract.