OBJECTIVE To compare cystopexy alone versus cystopexy with posterior pubourethral ligaments plication for the occurrence of postoperative stress incontinence after prolapse surgery, and to compare the two surgical series in terms of complications and urodynamic effects. METHODS One hundred two continent patients randomly underwent cystopexy alone (N = 52) or cystopexy with posterior pubourethral ligaments plication (N = 50). All had a urethrocystocele grade 2 or greater and a negative stress test with the prolapse repositioned. A full urodynamic investigation was repeated 6 months after surgery. RESULTS Twelve (23%) and 14 (28%) patients (P = .73) required intermittent self-catheterization for 11.1 +/- 5.1 and 16.5 +/- 11.1 days, respectively (cystopexy alone versus cystopexy with posterior pubourethral ligaments plication, P = .002). Long-lasting difficulties in voiding were present in zero and five (10%) patients (P = .02). One subject receiving posterior pubourethral ligaments plication underwent urethral dilation for complete urinary retention. At 1 year follow-up, four patients (8%) in each series developed postoperative stress incontinence (P = .62). Symptomatic detrusor instability complicated the postoperative course in one patient (2%) of each group. CONCLUSIONS Cystopexy alone implied lower morbidity in terms of resumption of spontaneous voiding and long-lasting difficulties in voiding. The procedure could be recommended as an effective and safe treatment for continent patients with severe urethrocystocele. Additional plication of the posterior pubourethral ligaments did not seem superior to cystopexy alone in preventing the postoperative occurrence of stress incontinence.