In this study we assessed the incidence of voiding dysfunction in women 6 months after undergoing a tension-free vaginal tape (TVT) procedure. Logistic regression was then used to look for significantly associated factors from a range of patient, urodynamic and surgical variables. From a group of 267 women we identified 22 (8%) who needed to perform daily intermittent self-catheterisation (ISC) as a result of the TVT surgery. When potential predictive factors were examined individually there were three that appeared to be associated with the need to use ISC: menopausal status,previous incontinence surgery and the centile score for average voiding flow rate (as derived from a volume--flow rate nomogram). Following multivariate logistic regression this flow rate centile score showed the strongest association with post-TVT voiding dysfunction, the likelihood of needing ISC increasing as the centile score fell. This factor has not previously been described but is readily assessed pre-operatively and may be useful in case selection for TVT.