As a result of the success of paediatric cardiology and cardiac surgery over the last three decades, there will shortly be more adults than children with congenital heart disease. An important issue is transiton of adolescents from paediatric to adult care with a clear management and follow-up plan. Patients’ follow-up care is stratified nto three levels depending on the patients’ cardiac conditions. Specialist service must provide also support for many psychosocial problems among this population. Arrhythmia is the main reason for hospitalization of grown-ups with congenital heart disease as well as an increasingly frequent cause of morbidity and mortality. Pharmacological treatment is often disappoiting. The success rate of caterer ablation is low because of scars and complicated and multiple arrhythmia circuits. Right to left shunts and the resulting hypoxemia and cyanosis in GUCH patients have profund haematological consequences which affect many organs. These patients have an increased risk of stroke, problems with haemostasis, impaired renal function, acne, etc. Adult patients with Eisenmenger syndrome have progressive reduction of effort tolerance and increased cyanosis. A general policy of “non-intervention”, unless absolutely indicated, is recommended to avoid destabilization of “balanced physiology”. Most grown-ups with congenital heart disease have a life-long risk of infective endocarditis and need antibiotic prophylaxis according to the European Society of Cardiology Task Force on infective endocarditis. Recommendations for exercise in this population need to be based on the ability of the patients as well as on the impact of physical training on cardiac haemodynamics. Exercise may have potentially harmful haemodynamic effects and arrhythmias. In Estonia, specialized care for GUCH patients is provided in the department of cardiac surgery of Tartu University Hospital.