Thirty-five patients with postoperative enteric and/or biliary fistulae were diagnosed and treated by percutaneous catheter drainage. All were initially considered to have postoperative abdominal abscesses, and the enteric or biliary communications were unrecognized before radiologic intervention. In addition, at the time of initial catheter insertion, only six of the 35 abscesses were recognized as being associated with an underlying fistula. In the other 29 patients the fistulae were found either by clinical follow-up or contrast sinogram after 24-72 hr of catheter drainage. Percutaneous catheter drainage was the definitive treatment in 28 (80%) of the 35 patients. The seven failures were either from inadequate catheter positioning or inability to treat the primary cause of the fistula (e.g., radiation enteritis, perforated cancer). These data suggest that even abscesses with underlying fistulae, traditionally an indication for surgical intervention, may be successfully managed by percutaneous methods.