Introduction.-In this retrospective audit of renal artery duplex ultrasounds (RADU), performed on 791 patients during a 2-year period, we analyze the clinical indications for testing, the patient cohort characteristics, and RADU results and outcomes. Results.-We found RADU to be sensitive and specific for the detection of renal artery stenosis with limitations in some instances attributable to physical interactions between ultrasound and body tissues and the variable presence of accessory renal arteries, even when performed by qualified experienced vascular sonographers. The results show the wide range of clinical indications for the performance of the test and document the multiple co morbidities of the patient population. Results show the majority of renal artery lesions are atherosclerotic in nature and that few patients go on to have renal artery intervention. The interventions do result in improvement of blood pressure but no change in resistive index. Conclusion.-The future role of RADU will be determined by medical research that provides evidence-based outcomes of the natural history of renal artery stenosis in the context of hypertension, allowing algorithms to be developed that best identify the medical versus interventional therapies for individual patients attempting to optimize renal function and blood pressure control while modifying associated risk factors. This will then allow more selective use of this diagnostic tool to answer more specified clinical questions on a case-by-case basis.