Within the last decade the prevalence of adult patients living with congenital heart disease equals that seen in children. This expanding population poses a challenge to clinical cardiologists who will be caring for patients with the clinical manifestations of this condition. Neonatal lupus is a model of passively acquired autoimmunity and is responsible for the majority of clinical cases of congenital heart block (CHB). This review will focus on the presentation, pathophysiology, and the long-term follow-up of CHB associated with neonatal lupus, and discuss important diagnostic tests, familial implications, and pacemaker issues associated with the care of an adult with CHB.