While a few decades ago only a minority of patients, particularly of those with complex congenital heart disease, could reach adulthood, progress of pediatric cardiology and cardiac surgery allows now the survival of the majority. Thus, adult cardiology is faced with a new challenging patient population. Since only a few congenital heart defects can be cured, regular follow-up during adult life is of major importance. Residual as well as consequently developed lesions must be recognized. Optimal timing of surgery or catheter intervention is necessary to provide the best long-term outcome. Despite optimal treatment part of the patients will develop long-term complications such as arrhythmias, pulmonary hypertension and, eventually, heart failure. Acute complications such as arrhythmias, aortic dissection or rupture, endocarditis, cerebral events due to embolism, bleeding or abscesses, and pulmonary embolism or bleeding must be recognized early and treated appropriately. Management of noncardiac surgery, pregnancy and delivery can be challenging. Another task is counseling regarding exercise and sports, choice of profession, driving and insurance issues. Finally, psychosocial issues must be taken into account for appropriate care of this special patient group.