The tensor fascia lata (TFL) muscle, together with the overlying skin of the anterolateral thigh, makes a reliable musculocutaneous unit. It can be lengthened safely by taking the fascia lata and the skin of the anterolateral mid and lower thigh to within 8 cm of the knee. The skin of the longer flap is supplied by large perforating musculocutaneous arteries, the terminal branches of the vascular pedicle of the muscle. The shorter flap can easily be transposed over the trochanteric area, while the larger flap will cover not only the trochanter but also the ischial and sacral areas. The flap serves equally well as a transposition, island, or free flap. The anatomical and vascular basis of the flap is presented, together with its application in 21 patients. Possible further applications of the flap, including anterior rotation, are discussed.