The semi free latissimus dorsi flap is characterized by a temporary vascular anastomosis on a pedicle not belonging to the loco-regional anatomy of the skin defect; after a period of autonomy, the section of the flap pedicle is obligatory. Its advantage compared to the classic free flap is the great microsurgical security avoiding complex, and stressful supervision in the postoperative period. From June 1998 to January 2001, 7 patients ranging from 18 to 65 years old and suffering from large scalp defects going between 20 x 13 cm and 27 x 18 cm have benefited from this surgical method. The etiology of these defects was: in 4 cases dermatofibrosarcoma protuberans involving the periost, in 1 case destruction of the near entirety of the scalp and calvarium by electrical burn, in 1 case an instable scar of burn with osteomyelitis and in the last case an osteomyelitis on a frontal cranioplasty. Three stages have been used:--The thoraco-dorsal artery was anastomosed on the wrist to the radial artery in a termino-lateral way and the thoraco-dorsal vein to the superficiel radial vein in a termino-terminal way;--The flap was fixed to the forearm for 2 weeks, then, the debridement which has always exposed the dura was done; The flap was sutured to the defect after reconstruction of calvarial defect with the méthylmétacrylate implant;--After 3 weeks the pedicle was sectioned and the flap tailored exactly to the defect. No postoperative complications were reported. With a mean follow-up of 18 months, the scalp coverage was very satisfactory.