The CONTROLRISK study was designed to determine the cardiovascular risk profile of the hypertensive population attended at primary care and specialist setting in Spain and to investigate whether physicians stratify the risk correctly, according to the 2003 European guidelines. A total of 8920 patients were recruited from primary care (n=4485) and specialist outpatient clinic (n=4435). The age criteria was 62.6+/-11.1 years; 51.6% were women. No differences were observed in the severity of hypertension. More than 85% presented other cardiovascular risk factors, similarly in both groups. Target organ damage (TOD) and associated clinical conditions (ACC) were more frequent in specialist setting (57.6 vs 34.3% and 39 vs 28.7%, both P<0.0001). The most common risk factor was age. The most frequently reported TOD was left ventricular hypertrophy (42.3 and 22.1%; P<0.0001). Ischemic heart disease was the most common ACC (21.5 vs 13.1%; P<0.0001). The risk profile was significantly higher in specialist population (75.1 vs 60.3% of patients belonged to high- or very high-risk groups). Specialists and primary care physicians stratified only 54.6 and 48% of their patients correctly, respectively (P<0.05). Both, specialists and general practitioners (GPs) strongly underestimated the risk. Very high-risk patients were adequately assessed only in 44.9% of cases by specialists and in 25.3% by GPs (P<0.001). More than half of the hypertensive patients attended by GPs in Spain belong to the high- or very high-risk groups. GPs and specialists tend to underestimate the cardiovascular risk in daily clinical practice, mainly in very high-risk patients.