Congenital heart defects (CHD) are cardiovascular malformations that generally occur due to aberrant development of a normal structure in the fetus, or failure of such a structure to progress beyond an early stage of embryonic or fetal development. Malformations are due to complex multi-factorial genetic and environmental causes. Congenital heart defects, in a definition proposed by Mitchell et al, is a gross structural abnormality of the heart or intrathoracic great vessels that are actually or potentially of functional significance. A comprehensive approach to every aspect of CHD, covering from embryology, fetal malformations, pathology, clinical approach, investigations, interventions to the surgery is very essential to reduce the morbidity and mortality in children with CHD.