Although the prevalence of hypertension in the paediatric population is rising, simultaneously with the rise in childhood obesity worldwide, hypertensive emergencies are unusual in clinical practice. A hypertensive emergency is defined as a severe hypertension and life-threatening event in the presence of acute target-organ lesions, requiring immediate intervention to reduce the blood pressure. Hypertensive urgency refers to severe hypertension without evidence of new or worsening end-organ injury. End-organ damage is defined as impairment in renal, myocardial functions and neurological manifestations derived from hypertension. Child’s doctors should pay attention to the paediatric patients who present with elevated blood pressure and related clinical hypertensive symptoms, especially headache, nausea/vomiting, and altered consciousness which may indicate that appropriate and immediate antihypertensive medications are necessary to prevent further damage. Severely hypertensive patients with acute end-organ damage (hypertensive emergencies) warrant admission to an intensive care unit for immediate reduction of blood pressure with a short-acting intravenous antihypertensive medication. Hypertensive urgencies (severe hypertension with no end-organ damage) may in general be treated with oral antihypertensive agents as an outpatient. Choice of the appropriate agent should be based on the underlying pathophysiological and clinical findings, on the mechanism of action, and on its potential side effects. This article focuses on some of the important aspects of paediatric hypertensive urgencies and emergencies, including common causes, important features of diagnosis and options for medical management.