OBJECTIVES Development of acute urinary retention (AUR) is common in the aging male. The pathophysiology of AUR is attributed primarily to prostatic obstruction. The objective of this study was to evaluate the risk of AUR in men after open radical prostatectomy (ORRP). METHODS A questionnaire asking whether a urinary catheter had been inserted after its initial removal was sent to 1361 men who underwent ORRP by a single surgeon (HL) between October 2000 and January 2007. Follow-up ranged from 12 to 84 months (mean, 48 months). For those who responded that a catheter had been reinserted, a follow-Lip question inquired specifically when this event occurred. The reason for postprostatectomy catheter reinsertion was determined via phone interview. RESULTS A total of 952 men (69.9% response rate) mailed a completed questionnaire to our database manager. No men underwent catheter reinsertion owing to spontaneous AUR. Ninety-two men (9.7%) answered "yes" to requiring catheter insertion postprostatectomy. The reasons for recatheterization were an intermittent catheterization regimen after dilation of an anastomotic stricture or meatal stenosis (n = 68), AUR immediately after initial catheter removal (n = 14), and elective reasons (n = 10). All urethral strictures were dilated within the first year after surgery and no patient with stricture presented with AUR. CONCLUSIONS The risk of spontaneous AUR after I month of catheter removal after ORRP is 0%. We believe that this is an important unrecognized clinical benefit of ORRP, especially in men with moderate to severe lower urinart tract symptoms or enlarged prostates, who are at higher risk for AUR.