The pattern of blood supply to the integument of the thigh is reported. A new technique is described for analyzing the length, direction, and number of arterioles in specimens of cadaver skin and deep fascia. The information obtained from these studies adds to existing knowledge of the anatomic vascular basis of direct cutaneous and musculocutaneous flaps in this region and provides a scientific basis for the elevation of fasciocutaneous flaps in such a way as to aid the achievement of maximum length-to-breadth ratios.