Atrioventricular nodal reentry tachycardia is a supraventricular tachycardia with a double nodal pathway between the atria and the ventricles located in the normal AV-node. It may cause a reentry circuit. Atrioventricular nodal reentry tachycardia is one of the most common supraventricular tachycardias in adulthood, but is seldom diagnosed in children--perhaps because of difficulties with diagnosing them. We have studied diagnostic criteria, clinical presentation, incidence, prognosis and treatment in children and adolescents.The article is based on the literature found in the databases PubMed and Medline. We used the search words atrioventricular nodal reentry tachycardia, AVNRT, permanent junctional reentry tachycardia, PJRT, supraventricular tachycardia, neonates, infants and children. Articles were also identified by examining the references.Atrioventricular nodal reentry tachycardia is rare during the first years of life, but becomes more frequent with age. There are few studies of this rhythm disturbance in children and reliable data on incidence, prognosis and prognostic variables are limited, especially for untreated cases. There are three main treatment regimens, acute and prophylactic medication and curative treatment with radiofrequency catheter ablation.