This study was designed to evaluate whether primary care physicians in Spain accurately diagnose the metabolic syndrome in hypertensive patients, to define the profile and management of these patients in clinical practice, and to ascertain the level of blood pressure and low-density lipoprotein cholesterol control. Data were analyzed from a cross-sectional survey involving 12,954 patients with hypertension (Prevención Cardiovascular en España en Atención Primaria: Intervención Sobre el Colesterol en Hipertensión [PRESCOT] study), wherein 52% of the cohort fulfilled the National Cholesterol Education Program-Adult Treatment Panel criteria for the metabolic syndrome. The majority of patients (54.6%) had 3 risk factors, 32.4% had 4, and 13% had 5 risk factors. Physician diagnosis of the metabolic syndrome was poor, with 43.7% of physicians missing the diagnosis and 12.9% wrongly diagnosing the metabolic syndrome. Blood pressure and low-density lipoprotein cholesterol control rates were very low, with only 4.7% of metabolic syndrome patients achieving control for both blood pressure and low-density lipoprotein cholesterol vs 13.5% for non-metabolic syndrome patients (P<.0001). These findings demonstrate that the metabolic syndrome is common in patients with hypertension and that it is generally poorly diagnosed and treated by primary care physicians.