Down syndrome is a genetic condition that occurs in approximately one in every 800 to 1,000 live births. It affects people of all ages, races and economic levels and is the most frequently occurring chromosomal abnormality. It occurs when there are three, rather than two, chromosomes present in every cell of the body. Instead of the usual 46 chromosomes, a person with Down syndrome has 47. It is this additional genetic material that alters the course of development and causes the characteristics associated with the syndrome. Down syndrome affects over 350,000 people in the United States alone. Recent advances in our understanding of Down syndrome have resulted in dramatic improvements in the life span and potential of those who are affected. People with Down syndrome are more like their nondisabled peers than they are different and they deserve the same opportuntiies.