The aim of this study was to specify certain anatomic features of the gracilis m. with a view to the use of muscular or myocutaneous flaps. It was based on dissection of 84 gracilis muscles in 42 subjects as well as selective injection of the main pedicle of 20 muscles. This established the following points: 1) The arterial supply is abundant, consisting of several pedicles reaching the muscle on its deep aspect. The main neurovascular pedicle arises from the deep vessels of the thigh, via either the a. of the adductors (73%), the medial circumflex a. (19.2%) or as a double supply from both arteries (7.7%); 2) The cutaneous vascularisation over the gracilis m., derived from the solitary main pedicle, is inconstant. In 20 injections, it was satisfactory in 11 cases, poor in 5 and absent in 4; 3) The distal tendon of the gracilis m. is closely related to the posterior branch of the saphenous n. to the leg, which it crosses in an elongated X; 4) A simple method of calculation based on the distance between the upper border of the pubis and the medial femoral epicondyle allows quite precise determination of the point of entry of the main pedicle into the gracilis m. 5) Complete dissection of the main pedicle adds to the available length of the muscle flap.