This chapter provides an overview of Down syndrome, dysmorphology and genetic counseling. Down syndrome is the most common chromosomal disorder seen in children for which parents often seek pediatric consultation. All children with Down syndrome should be evaluated for other systemic malformations which require immediate management. Cardiovascular examination includes echocardiography to look for cardiac malformations. The most important malformations associated with Down syndrome are atrioventricular septal defects (AVSD), ventricular septal defects (VSD), atrial septal defects (ASD) and tetralogy of Fallot (TOF). Congenital hypothyroidism is seen in about 5% children with Down syndrome. The word \"dysmorphology\" was coined by Dr David Smith in the 1960s to describe the study of human congenital malformations. A \"birth defect\" is an abnormality of structure, function or metabolism present at birth that results in physical or mental disability or is fatal. Normal variant is applied to those features that fall at the far end of normal distribution. Minor malformation is that malformation which does not cause any functional defect, e. g. preauricular tag, isolated polydactyly, digiti minimi, etc. A malformation is due to a defect in embryogenesis. Examples include cleft palate and anorectal malformation. Genetic counseling is a communicative process, which deals with human problems associated with the occurrence and/or recurrence of a genetic disorder in a family. This process involves an attempt by one or more appropriately trained persons to help the individual or family to comprehend the medical facts, including diagnosis, probable course of the disorder and available management and to appreciate the way heredity contributes to the disorder and the risk of recurrence in relatives and siblings. The important principles of genetic counseling are confirmation of diagnosis in the proband, communication, nondirectiveness, truthfulness and timing of genetic counseling.