BACKGROUND: Urinary incontinence is a common long-term complication after radical prostatectomy. Spontaneous recovery of normal urinary control after surgery can take 1-2 years. We aimed to investigate whether there was any beneficial effect of pelvic-floor re-education for patients with urinary incontinence as a result of radical prostatectomy. METHODS: 102 consecutive incontinent patients who had had radical retropubic prostatectomy for clinically localised prostate cancer and who could comply with the ambulatory treatment schedule in our hospital were randomised, after catheter removal, into a treatment group (n=50) and a control group (n=52). Patients in the treatment group took part in a pelvic-floor re-education programme for as long as they were incontinent, and for a maximum of 1 year. The control group received placebo therapy. The primary endpoint was continence rate at 3 months. Incontinence was assessed objectively with the 1 h and 24 h pad tests and subjectively by the visual analogue scale. The groups were analysed on an intention-to-treat basis by ANOVA and chi2-test. FINDINGS: In the treatment group continence was achieved after 3 months in 43 (88%) of 48 patients. In the control group, continence returned after 3 months in 29 (56%) of 52 patients. At 1 year, the difference in proportion between treatment and control group was 14% (95% CI 2-27). In the treatment group improvement in both duration (log-rank test, p=0.0001) and degree of incontinence (Wald test, p=0.0010) was significantly better than in the control group. INTERPRETATION: Pelvic-floor re-education should be considered as a first-line option in curing incontinence after radical prostatectomy.