Background. The prevalence of leg ulcer disease in Ireland has been poorly documented. Aims. This study aimed to investigate the aetiology and prevalence of leg ulcers in one health district. Methods. All patients receiving healthcare for an active leg ulcer in the Mid-Western Health Board (MWHB) region of Ireland (population: 317,069) were identified in a defined two-month period. A cross-sectional survey of all healthcare workers providing care to patients with leg ulceration was carried out. Patients with leg ulcers of uncertain cause were invited for follow-up assessment to establish the underlying cause. Results. There were 389 patients with leg ulcers with a mean (standard deviation [SD]) age of 72.3 (11.1) years. The prevalence was 0.12% but it was 1.03% in patients aged 70 years and over. Women were twice as likely to be affected. Venous disease accounted for 81% of ulcers, and arterial disease for 16.3%, while ulceration due to diabetic neuropathy and rheumatoid vasculitis was unusual. Conclusion. Leg ulcers are an important source of morbidity in our ageing population. Effective treatment programmes could diminish the impact of this debilitating disease on the health service.