- Canadian Down Syndrome Society
- Down Syndrome Association of Peterborough formerly known as C.H.A.N.G.E.S. (Children and Adults for Normalization, Growth, Equality, and Socialization)
- Down Syndrome Health Issues
- Down’s Heart Group (DHG) a charity offering support and information relating to heart conditions associated with Down’s Syndrome. [UK]
- Journal of Down Syndrome & Chromosome Abnormalities
- National Down Syndrome Congress The NDSC works to empower its members and all people with Down syndrome by creating a national climate in which all people will recognize and embrace the value and dignity of people with Down syndrome.
- National Down Syndrome Society is a national advocate for the value, acceptance and inclusion of people with Down syndrome.
- National Association for Down Syndrome NADS is the oldest organization in the country serving individuals with Down syndrome and their families.