The prognosis of congenital heart disease (CHD) has improved, and most patients now reach adulthood. Owing to residual disease and comorbidities, it is recommended that adult CHD (ACHD) patients transition to adult care for lifelong monitoring and treatment. However, this transition period can be challenging for CHD patients owing to obstacles such as independence from their parents and establishing self-management. To achieve a seamless shift from pediatric to adult care and ensure continuity, it is important to educate and motivate patients appropriately, and an established transition system is needed that involves collaboration between CHD specialists and healthcare providers across medical specialties. The present review describes the epidemiology of ACHD and notable points in patient care as the background of transition. The concepts and an overview of transition systems, educational systems, and potential lapses in the care of their relevant causes are then provided with supporting evidence.