Management of complex perineal fistulas such as high perianal, rectovaginal, pouch-vaginal, rectourethral, or pouch-urethral fistulas requires a systematic approach. The first step is to control any sepsis with drainage of abscess and/or seton placement. Patients with large, recurrent, irradiated fistulas benefit from stoma diversion. In patients with Crohn's disease, it is essential to induce remission prior to any repair. There are different approaches to repair complex fistulas, from local repairs to transperineal and transabdominal approaches. Simpler fistulas are amenable to local repair. More complex fistulas, such as those secondary to irradiation, require interposition of healthy, well-vascularized tissue. The most common flap used for this treatment is the gracilis muscle with good outcomes reported. Once healing is confirmed by imaging and endoscopy, the stoma is reversed.