Many procedures are used to treat internal (IRP) and external rectal prolapse (ERP). We report the outcome of surgery tailored in accordance with an evolving Unit algorithm over a 21-year period. Two hundred and sixty-eight patients (151 IRP and 117 ERP) are reported. Perineal procedures (Delorme's mucosectomy, Altemeier's perineal rectosigmoidectomy) were used in frail elderly patients with ERP with abdominal sacrorectopexy or the Frykman-Goldberg procedure in fit patients. In IRP, prolapsectomy was most common with anterior hemi-Delorme's procedures for rectocele and levatorplasty for coincident faecal incontinence. Clinical and functional outcome was assessed over a median of 61 months (range 4-184 months). Postoperative mortality was 0.4%. For ERP, a perineal procedure was carried out in 75 (61.4%) cases with a 7.2% complication rate, postoperative incontinence in 20 (26.7%), constipation in four (5.3%) and recurrence in 12 (16%). For 42 abdominal procedures, the complication rate was 5% with incontinence in 7.1%, constipation in eight (19%) and recurrence in five (11.9%). A perineal operation was used in 89.4% of patients with IRP with incontinence in 10.6%, persistent constipation in 48 (52.7%) and recurrence in 25 (27.5%). The overall incontinence rate was 11% following abdominal and 24% following perineal procedures (P < 0.05). Recurrence of ERP was significantly higher following a perineal operation (P < 0.05). Tailored surgery for ERP achieves satisfactory results in terms of recurrence and functional outcome. For patients with IRP, perineal procedures are associated with a high incidence of recurrence and residual evacuatory difficulty.