This document provides an overview of hypertensive crises, including hypertensive urgency and emergencies. It defines these conditions, discusses their epidemiology, risk factors, pathophysiology, clinical presentation, diagnosis, and management. Hypertensive urgency involves severe blood pressure elevations without end-organ damage, while emergencies involve elevations with end-organ damage. Management of urgency involves gradually lowering blood pressure over hours to days, while emergencies require faster reduction, usually with parenteral drugs initially then oral medications. Follow up aims to identify and treat underlying causes while achieving blood pressure control to prevent recurrence.