Cardiomyopathy refers to a diverse group of myocardial diseases with multiple causes. In 1995, the World Health Organization classified cardiomyopathies into hypertrophic, dilated, restrictive, and mixed type. This classification is based on the pathophysiology of the disease. However, with rapid evolution of molecular genetics in cardiology, the American Heart Association in 2006 has classified cardiomyopathies into two major groups based on predominant organ involvement and etiology; Primary cardiomyopathies are those solely or predominantly confined to heart muscle and are relatively few in number. Secondary cardiomyopathies show pathologic myocardial involvement as part of a large number and variety of generalized systemic (multiorgan) disorders.Current evidence supports the use of genetic testing in clinical practice to improve risk stratification for clinically affected patients and their at-risk relatives for cardiomyopathies.