Interstitial cystitis, an enigmatic chronic pelvic pain syndrome that occurs primarily in women, is much more common than originally believed. Its etiology is unknown, its evaluation and diagnosis remain controversial, and its treatment is largely empiric. Recent basic and clinical research is unlocking some of the mystery surrounding this clinical syndrome. Diagnostic awareness, willingness to consider recently studied therapies, and reasonable therapeutic expectations on the part of both the physician and the patient seem to be the key to successful management of this condition.