Cardiomyopathies are a heterogeneous group of primary diseases of the myocardium usually of genetic origin and with familial presentation. The identification of multiple genetic causes for these diseases has opened a new window for early diagnosis, understanding of their natural history and improvement in risk stratification and management. However, in the past years, the clinical application of genetics has been limited by the prohibiting cost and restricted yield of the available genotyping technologies. The emergence of Next Generation Sequencing (NGS) has completely changed this scenario. This group of sequencing technologies allow the evaluation of hundreds or even thousands of genes in parallel at an affordable cost. Now the challenge is not genotyping per se but the interpretation of the complex results that NGS generates. In this paper we review the main aspects related to the application and impact of Next Generation Sequencing in the study of cardiomyopathies: technology, analysis procedures, bioinformatics, clinical validation and interpretation of results.