The increased hospital stay and excess hospitalization costs that resulted from Foley catheter-associated urinary tract infection after 5 common surgical procedures were evaluated in a case-matched and controlled study. Nosocomial urinary tract infections increased postoperative hospital stay by an average of 2.4 days (p equals 0.017) and increased hospital costs by $558 per patient. Recommendations for prevention of urinary catheter-associated infections can be assessed accurately by comparison to the parameters of morbidity and cost.