Bladder involvement is common in transverse myelitis but its characteristics and natural history, particularly in relation to neurological outcome, have not been described in a paediatric population previously. Ten children, with ages ranging from 8 months to 16 years, who had a diagnosis of acute transverse myelitis were studied with video urodynamics and followed up in a tertiary paediatric neurourology clinic. Nine of ten children had obstructive urinary tract symptoms at presentation and all went on to develop ‘irritative’ urinary tract symptoms (frequency and urgency) about 1 month after initial presentation. Video urodynamics showed a combination of irritative (detrusor hyperreflexia) and obstructive (detrusor–sphincter dyssynergia) abnormalities in most patients and enabled management to be specifically directed towards these. The patients progress was followed up for a median duration of 36 months. All had residual bladder dysfunction, only four were asymptomatic on treatment. The degree of recovery of bladder function was not related to the degree of motor recovery.