NADD is a not-for-profit membership association established for professionals, care providers and families to promote understanding of and services for individuals who have developmental disabilities and mental health needs. The mission of NADD is to advance mental wellness for persons with developmental disabilities through the promotion of excellence in mental health care.

NADD is recognized as the world’s leading organization in providing educational services, training materials and conferences. NADD has been influential in the development of appropriate community based policies, programs and opportunities in addressing the mental health needs of persons with ID/D.