A double-blind study of terodiline compared with placebo was performed in 58 children aged 6 to 14 years with urgency or urge incontinence. All had an unstable bladder at cystometry. A bladder regimen was emphasised during the study. Continence was improved according to micturition charting and a pad test in both groups. Terodiline at 25 mg/day, however, gave significantly better results than placebo. In patients with a subnormal bladder capacity (less than or equal to 150 ml), a significant increase in capacity was recorded on cystometry during medication with terodiline but not with placebo. The improved continence seen in the placebo group was probably due to the non-specific bladder training achieved by the child's increased awareness and adult involvement during treatment. The even better results attained in the terodiline group shows this drug to be a valuable adjunct to a bladder regimen in children with urge incontinence, particularly since no important adverse effects were noted during an 8-week period.