Between 1981 and 1986, transanal rectal advancement flaps were employed in the surgical management of 39 anorectal fistulas at the Cleveland Clinic. Included were 23 low rectovaginal, 12 fistulas-in-ano and, four rectourethral fistulas. Nineteen fistulas occurred in patients with Crohn's disease while the other 20 included 11 due to obstetric or surgical injury. This technique has become the Clinic's standard management for low rectovaginal fistulas but is reserved for complex fistulas-in-ano. Active proctitis or malignancy are contraindications to the procedure. Surgery requires elevation of a broad-based rectal flap, curettage of the tract, and advancement and primary suture of the flap over the internal opening. Fistulas were eradicated in 27 cases (69.2 percent) including 11 of 19 due to Crohn's disease (57.9 percent) and 16 of the 20 (80.0 percent) from other causes (mean follow-up, 25 months). Rectovaginal fistulas healed in 60.0 percent of those with Crohn's disease compared with 76.9 percent of those due to other causes. Complex fistulas-in-ano in Crohn's disease did less well. Only two of six of these fistulas healed. Temporary stomal diversion was used on nine occasions and a successful outcome was achieved in only four, indicative of the greater complexity of these cases. It is concluded that the transanal rectal advancement flap can be an effective method of repair for fistulas of the anorectal region including selected cases due to Crohn's disease.