Objective To compare open Burch colposuspension using sutures with laparoscopic colposuspension using mesh and staples in women with stress urinary incontinence. Design Multicentre, prospective randomised trial.Setting Departments of Obstetrics and Gynaecology, Sahlgrenska University Hospital, Göteborg, Borås County Hospital and Ö rebro University Hospital, Sweden. Population Women with genuine stress urinary incontinence or mixed incontinence with a predominantly stress component were included, and were randomised to either open colposuspension (n ¼ 120) or laparoscopic colposuspension (n ¼ 120). Methods Women were randomised to open colposuspension with sutures or laparoscopic colposuspension with polypropylene mesh and staples. Anaesthesia/operation time, blood loss, complications and other related surgical parameters were compared. Main outcome measures Objective and subjective cure rates from 48-hour frequency -volume chart, a 48-hour pad test and a subjective assessment of the woman's incontinence and quality of life performed one year after surgery. Results Objective and subjective cure rates were higher after open compared with laparoscopic colposuspension (P < 0.001). Quality of life was improved following surgery in both groups (P < 0.0001) and the improvement was significantly greater in the open colposuspension group (P < 0.05) with regard to physical activity. Performing an open colposuspension was less time consuming (P < 0.0001), resulted in more blood loss (P < 0.0001), longer catheterisation time (P < 0.01), greater risk of urinary retention (P < 0.01) and a longer hospital stay (P < 0.0001) compared with performing a laparoscopic colposuspension. The rate of serious complications was low in both groups. Conclusion Open colposuspension had a higher objective and subjective cure rate one year after surgery but with a greater blood loss, greater risk of urinary retention and a longer hospital stay than laparoscopic colposuspension.