Hypertrophic cardiomyopathy is one of the most common inherited cardiovascular diseases and is characterized by a heterogeneous appearance and natural history. Although previously thought to be a disease of the young, HCM is frequently diagnosed in patients over age 50. A careful history and physical examination and readily available non-invasive testing will diagnose most cases, but genetic testing can identify those not expressing the typical phenotype. Treatment of symptomatic patients is targeted toward improving LV diastolic function; for patients with the obstructive form HCM, treatment involves relieving outflow tract obstruction. Identification of those at risk for sudden death may require consideration of prophylactic defibrillator placement.