The Chromosome 18 Registry & Research Society is an advocacy organization composed primarily of the parents of individuals with a chromosome 18 abnormality. We consist of four separate organizations located in the United States, Canada, Australasian, and Europe, all with a common mission: To help people with chromosome 18 abnormalities overcome the obstacles they face so they may lead happy, healthy, and productive lives. We are proud to count among our members those who are affected by a chromosome 18 abnormality, extended family members, and professionals. Membership is free and open to any interested person. We are a 501(c)(3) non-profit, tax-exempt public charity.