Adult congenital heart disease (ACHD) patients represent a special population in modern cardiology: though their numbers are growing, and they represent a high-resource utilization subgroup, a robust evidence-base of randomized trials is lacking. Much of the standard therapy is adapted from the treatment of ischemic and idiopathic left ventricle systolic failure, with a small, but growing body of evidence on medical therapy in select ACHD diagnoses. At our institution, for instance, there is a long tradition of using angiotensin antagonists in patients with a systemic right ventricle to prevent deleterious remodeling. The effects of beta-blockers on functional class in ACHD are yet unproven, but there is promising data on pulmonary vasodilators. Control of coronary risk factors and aerobic exercise should be considered for all. Prevention of arrhythmias is important, and multi-site pacing is an emerging therapy. New prognostic tools including natriuretic peptides and CPET are increasingly used to guide earlier initiation of these therapies.