Amyloid cardiomyopathy should be suspected in any patient who presents with heart failure and preserved ejection fraction. In patients with echocardiographic evidence of ventricular thickening and without a clear history of hypertension, infiltrative cardiomyopathy should be considered. If imaging suggests the presence of amyloid deposits, confirmation by biopsy is required, although endomyocardial biopsy is generally not necessary. Assessment of aspirated subcutaneous fat and bone-marrow biopsy samples verifies the diagnosis in 40-80% of patients, dependent on the type of amyloidosis. Mass spectroscopy can be used to determine the protein subunit and classify the disease as immunoglobulin light-chain amyloidosis or transthyretin-related amyloidosis associated with mutant or wild-type TTR (formerly known as familial amyloid cardiomyopathy and senile cardiac amyloidosis, respectively). In this Review, we discuss the characteristics of cardiac amyloidosis, and present a structured approach to both the assessment of patients and treatment with emerging therapies and organ transplantation.