Because hypertension is common and many tests are available, an uncritical approach to laboratory and radiologic evaluation leads to unnecessary expenses. However, in most patients, accurate blood pressure measurement, a focused history and physical examination, and a handful of basic tests are enough. In this review we address the key questions in the evaluation of the patient with an elevated pressure reading, ie, does the patient have sustained high blood pressure? And if so, is the hypertension primary or secondary, are other cardiovascular risk factors present, and is there evidence of target organ damage?