Recent estimates place the prevalence of Down syndrome at 1 in 691 births, making it the leading known genetic cause of intellectual disability. This presentation provides an update on what is known about Down syndrome, its impacts on the individual and the family, and possible treatments. With Leonard Abbeduto, Ph.D., Andrea McDuffie, Ph.D., Angela John, Ph.D., Marie Moore Channell, Ph.D., Heather Green, and Robert Hulse. (#25992)