Secondary forms of hypertension are not uncommon in clinical prac­ tice, but they are often overlooked or forgotten by clinicians in many fields of medicine. Dr. George Mansoor' s volume on Secondary Hyper­ tension is an important contribution to the field of clinical hypertension and vascular diseases, since it brings up to date the numerous diagnostic and therapeutic advances in the evaluation for secondary types of hyper­ tension. In the past, textbooks usually stated that an etiology could be determined in less than 5% of patients presenting with newly diagnosed hypertension. We now know this is far too low a proportion (e.g., pri­ mary hyperaldosteronism alone may account for hypertension in 5% of patients presenting with chronic elevations in blood pressure). Secondary Hypertension has been thoughtfully organized into chap­ ters evaluating screening and diagnosis, as well as medical and/or sur­ gical intervention of the well-known etiologies of secondary hypertension in adults and children. Additional coverage is given to such exogenous or lesser appreciated causes of secondary hypertension as obstructive sleep apnea and drugs. These sections make this book novel because in the past little attention has been paid to the effects of noncar­ diac drugs that interfere with antihypertensive therapy or to exogenous substances that might induce refractory hypertension.