Congenital heart disease is the most common birth defect. Outcomes for congenital heart disease have improved greatly over the past several decades leading to an increase in adults with congenital heart disease. Cardiac MRI is an essential imaging tool for the evaluation of the adult with congenital heart disease. This chapter will discuss the utility of cardiac MRI in this patient population. A case-based approach will be used to illustrate the anatomy and physiology of common lesions. The post-operative assessment of several common interventions will also be investigated.