A six-year-old girl with surgically corrected imperforate anus and chronicfaecal soiling was successfully treated by biofeedback. A portable biofeedbackmachine using an anorectal balloon was constructed and lent to the patient’smother who administered the treatment at home following instruction in theclinic. Faecal incontinence was replaced by normal bowel evacuation habitsafter four weeks of the procedure. The effect was durable at least untilfollow-up at three months. Positive spin-offs were observed. The reversal ofthe child's encopresis suggested neuromuscular intactness of the anorectalregion despite the congenital malformation. Biofeedback probably compensatedfor an earlier learning fault. Domiciliary, parent-mediated biofeedbacktherapy is a cost-effective procedure and may be widely applicable to suitablepatients within the population of children with primary expulsive and retentivebowel control disorders.