Developmental Disabilities Institute

Developmental Disabilities Institute (DDI) was founded in 1961, to address the special needs of children with Autism and other developmental disabilities, and provide therapeutic intervention. Today, DDI is a non-profit, multi-site agency serving over 1,500 children and adults with Autism and related disorders, providing educational, residential, day habilitation and vocational services, as well as medical and dental services to over 5,000 patients through our Opti-Healthcare division across Long Island, NY.



DDI’s educational, residential day habilitation and vocational offerings are as diverse as the people we serve. Due to this, we have grown to include 5 main campuses located in Smithtown, Huntington, Medford, Riverhead and Ronkonkoma, NY, as well as 30 residential and day habilitation sites. Through almost 50 years of sustained effort, DDI has become widely known in our area. Today, we are the largest provider of services and programs for children and adults with Autism on Long Island.



The goal of our agency is to recognize the needs of each individual, while maintaining the highest standards of teaching and training for our children, their families, and our staff. DDI prides itself on being in the forefront of the most effective methods in use today for the treatment of Autism and related disorders. Our Mission Statement is “To support children and adults with developmental disabilities in achieving a lifetime of growth through exceptional care and innovative, individualized service.”