The occurrence of micturition complaints as late sequelae of multiple sclerosis is well studied and documented. However, no reports exist on urologically asymptomatic patients with a relatively short disease duration. In a prospective study of 40 patients with definite multiple sclerosis (mean disease duration 5 years), urodynamic investigations (cystometry and pressure-flow study) were combined with neuro-urophysiological measurements (cortical evoked potentials and sacral reflex latencies). Patients with (13) and without (27) micturition complaints were investigated. Neurourodynamic abnormalities were seen in 35 of 40 patients (88%). The lower urinary tract proved to be afflicted by multiple sclerosis at an early stage of the disease. Early neurourodynamic investigations had clinical implications. All of the complaining and half of the noncomplaining patients showed urodynamic abnormalities upon which the need for further followup and eventual therapeutic intervention was based. We conclude that neurourodynamic testing of a urinary functional system can be worthwhile as part of the initial diagnostic evaluation in patients with proved multiple sclerosis.