Our Story

NADD is an international association for persons with intellectual/developmental disabilities and mental health needs, comprised of individuals, families, and support professionals dedicated to enhancing the understanding and treatment of people experiencing co-occurring intellectual/developmental diagnoses (IDD) and mental health conditions or mental illness (MI).


To promote leadership in the expansion of knowledge, training, policy, and advocacy for mental health practices that promote a quality life for individuals with dual diagnosis (IDD/MI) in their communities.

We are a nonprofit organization dedicated to being a resource for individuals with intellectual disabilities, families and the IDD/MI professional industry.

  • We are the international experts in the IDD/MI Dual Diagnosis industry and field of study
  • We have been training and consulting for close to 40 years
  • We have been hosting annual conferences for nearly 4 decades
  • We have published over 70 books
  • We publish a professional research journal
  • We accredit organizations 
  • We certify individuals (DSPs, Clinicians and Dual Diagnosis Specialists)
  • We are a membership organization
  • We are the professional home for the IDD/MI industry’s top scholars, researchers, educators, behavioral health professionals, psychiatrists, psychologists, MCO’s, direct service providers, etc.
  • We serve as a critical resource for individuals, organizations, state governments and federal policy

Through all of our work, we promote whole person care through the biopsychosocial approach to treatment. 

We support and contribute to cutting edge research & training, public policy and advocacy, and the development of supports and treatment approaches that promote independence and full inclusion for people receiving services. 

7-Fold Strategy

  • We encourage the dissemination and exchange of pertinent information.
  • We promote educational and training programs.
  • We foster the development of appropriate resources and services.
  • We advocate for appropriate governmental policies.
  • We support research focused on identification, diagnosis, and treatment.
  • We seek to stimulate public and professional interest.
  • We seek to establish a vision of mental wellness.

We recognize and support through our services the need for a sustained effort by the professional community to meet the mental health needs of persons who have IDD, and we encourage an appreciation of the person’s ability to learn and develop as well as a focus on his/her inner life, needs, strengths, and motivation.

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