Acute uncomplicated cystitis is a common and costly disorder in women, and there is considerable variation in the diagnostic strategies currently used in clinical practice. Because the diagnosis of cystitis can be established in most patients using the history alone, the clinician's responsibility is to determine which patients require additional diagnostic testing. Patients with typical symptoms (i.e., dysuria, frequency, urgency, hematuria), without risk factors for complicated infection or pyelonephritis, and without a history of vaginal discharge, have a very high probability of cystitis and are appropriate candidates for empiric treatment. It is more difficult, however, to rule out infection in patients with suspected cystitis. Because the prevalence of culture-proven infection is very high in women who present with >or=1 symptom, and because the treatment threshold for this condition is low, a urine culture is generally required to rule out infection in patients with atypical symptoms, even in the presence of a negative dipstick test. In population-based, before-and-after studies, use of diagnostic algorithms has been shown to significantly decrease the use of urinalysis, urine culture, and office visits while increasing the percentage of patients who receive recommended antibiotics. These strategies have substantially reduced the cost of managing cystitis without an increase in adverse events or a decrease in patient satisfaction. Randomized controlled trials are needed to more closely examine the outcomes, costs of care, and patient satisfaction from different diagnostic and management strategies.