Introduction and hypothesis: The aim of this study was to determine whether preoperative voiding detrusor pressures were associated with postoperative outcomes after stress incontinence surgery. Methods: Opening detrusor pressure, detrusor pressure at maximum flow (pdet Qmax), and closing detrusor pressure were assessed from 280 valid preoperative urodynamic studies in subjects without advanced prolapse from a multicenter randomized trial comparing Burch and autologous fascia sling procedures. These pressures were compared between subjects with and without overall success, stress-specific success, postoperative detrusor overactivity, and postoperative urge incontinence using independent sample t tests. Results: There were no clinically or statistically significant differences in mean preoperative voiding detrusor pressures in any comparison of postoperative outcomes. Conclusions: We found no evidence that preoperative voiding detrusor pressures predict outcomes in women with stress predominant urinary incontinence undergoing Burch or autologous fascial sling procedures. © The Author(s) 2010.