After a short historic review of conceptual developments in hypertrophic cardiomyopathy, the natural history of the disease is analyzed according to each of its morphologic and functional abnormalities. The lack of association between hypertrophic morphology and sudden death is considered. Diastolic dysfunction and LV obstruction, although a frequent cause of dyspnea and heart failure, is not a risk factor for sudden death. Something similar occurs with the infrequent appearance in this disease of contractile failure. Myocardial ischemia is frequent in hypertrophic cardiomyopathy and general prognostic information about it is still lacking. Nevertheless, in young patients with family history of sudden death, a positive Thallium effort test may be a marker of sudden death (without an arrhythmogenic substrate), and may respond to verapamil. Finally, the new knowledge about genetic mutations in hypertrophic cardiomyopathy are analized. We conclude with some futuristic comments about hypertrophic cardiomyopathy.