Transient or permanent hypertension may result from the inappropriate activation of the sympathetic nervous system and/or from chronically elevated levels of circulating catecholamines (epinephrine or norepinephrine). Recent data implicate this high sympathetic tone as a contributing factor to the genesis of essential hypertension in a significant proportion of individuals, and show that it is frequently associated with insulin resistance and cardiovascular comorbidity. Among the several causes of catecholamine-mediated hypertension, pheochromocytoma, although rare, holds a special place and represents a challenging experience for the clinician. Diagnosis and therapy of this remarkable disease will be reviewed here in details, with a special emphasis on recent findings such as the high diagnostic sensitivity of plasma fractionated metanephrines, the better understanding of genetic diseases predisposing to chromaffin tumor development, and the modern management of pheochromocytoma, including the medical preparation before surgery. Other causes of catecholamine excess will be reviewed more briefly.