OBJECTIVE: To describe the prevalence of urinary incontinence and to find characteristics useful in general practice for identifying middle-aged and elderly women with the problem. DESIGN: Cross-sectional interview study. SETTING: Population-based samples of Danes. SUBJECTS: A total of 5795 women older than 45 years (46+ years). MAIN OUTCOME MEASURES: Prevalence of incontinence and clinical characteristics assessed by standardized interview questions. RESULTS: The overall prevalence of urinary incontinence was 20% among women less than 60 years of age and 44% among those older than 80 years. Increasing age was highly associated with both forms of incontinence (stress and urge). High body mass index (BMI), chronic lung disease, and stroke were also associated with both forms, while number of children was associated with stress incontinence only. Predictive models show that 56% of women characterized by high age (older than 80 years) and overweight (BMI higher than 30) will suffer from urinary incontinence. The low-risk group defined by these two parameters (aged 46-60 years and not overweight) still had a 19% prevalence in the last month. CONCLUSION: The prevalence of urinary incontinence increased with age. Even in the low-risk groups the problem was very common in old age. Questions about incontinence should, therefore, be asked in relevant consultations with all elderly female patients.