The objective of this study was to compare porcine dermal sling (Pelvicol implant, Bard) with tension-free vaginal tape (TVT) in the surgical treatment of stress incontinence. One hundred and forty-two women with genuine stress incontinence (GSI) were randomly assigned to either Pelvicol implant pubovaginal sling (n=74) or TVT (n=68). They were followed up at a minimum of 6 months (range 6-24 months), with a median follow-up of 12 months. The majority (n=109) of procedures were carried out in a day surgery unit. The median operation time was 35 minutes (range 15-60) in the TVT group and 30 minutes (range 20-80) in the Pelvicol implant group; 81% of the TVT group and 77% of the Pelvicol implant group were able to void urine within 24 hours, and had insignificant residual bladder volumes. The prevalence of postoperative symptomatic voiding dysfunction was 3.4% after TVT and 1.4% after Pelvicol implant. Nine percent of the TVT group developed de novo urge incontinence and 6% of the Pelvicol implant group had de novo urge incontinence 6 months after the procedure. Postoperative evaluation was done at the outpatient department, and a postal questionnaire was also completed to determine subjective continence status. The patient-determined cure rate was 85% in the TVT group and 89% in the Pelvicol implant group. The Pelvicol implant sling had a comparable patient- determined success rate with TVT and should be considered in the surgical treatment of women with genuine stress incontinence.