The symptoms of hypertrophic cardiomyopathy (HCM) result from a combination of high filling pressures (“backward” heart failure) and low cardiac output (“forward” heart failure). The mainstay of noninvasive testing in symptomatic patients with HCM is transthoracic echocardiography. The detection of concomitant coronary artery disease (CAD) as a cause of symptoms may be difficult by clinical assessment and exercise testing; cardiac computerized tomographic angiography (CTA) has emerged as the most useful noninvasive test for the assessment of potentially ischemic symptoms due to CAD. Cardiac catheterization is useful for documenting right-sided pressures and cardiac output; determining whether a left ventricular outflow tract (or midcavity) gradient is present at rest or with provocation; separating aortic valvular from subvalvular and supravalvular gradients; determining whether CAD is present; and excluding other pathologic causes of left ventricular thickening. Cardiopulmonary exercise testing provides quantification of functional capacity and distinguishes between cardiac and pulmonary contributions to symptoms.