1966 - A group of parents, seeking services for their children with Down syndrome, found The Association for Special Children. Early intervention strategies were developed with the aid of outside consultants.

1972 - 73 - Space was rented in Nassau and Suffolk for the first “center-based” programs. The first teacher and teacher assistants were hired, paid through private fundraising efforts.

1975 - PL 94-142, Education of All Handicapped Children Act, is passed marking the beginning of government funding for special education.

1975 -76 - The agency is approved for New York State funding, the programs are consolidated in Eastern Nassau County, and the salaried position of Executive Director is created.

1978 – 1980 - Preschool moves to Bellmore. School grows to 70 students and becomes a practicum site for local universities. Budget reaches $250,000 with 26 full and part time staff.

1984 - Governor Cuomo establishes October as Down syndrome Awareness Month in New York in a ceremony attended by Executive Director Freda Stimell.

1985 – 86 - School expands with new classes added; enrollment reaches 90 students.

1986 – 88 - 5Plus after school recreation program started with legislative grant. Expands to Saturdays and Program Coordinator is hired in 1988. First bilingual assistant is hired.

1992 – 1993 - For the first time, 100% of ACDS graduates transition to public school placements. First full-time controller is hired.

1995 – 96 - Inclusionary day care program for children in the community opens.

1996 – 1997 - First children without Down syndrome are accepted into program.

1999 - Agency name is changed to Association for Children with Down Syndrome, Inc., also legally known as ACDS. School moves to current leased facility in Plainview.

2000 - First Individualized Residential Alternative (IRA group home) opens in Wantagh – all six residents are former ACDS students. Two other homes quickly follow in Freeport and Seaford and full-time position of Director of Adult Services is created.

2002 - 2003 - ACDS begins services to children on the Autistic spectrum with a center based socialization and communication class in the Early Intervention (EI) program. Merrick IRA opens.

2004 - 05 - Michael Smith is hired as Executive Director and Chief Financial Officer position is created. Horatio Avenue IRA opens in Merrick. – for the first time 2 residents are not ACDS alumni. Adult Medicaid Service Coordination program begins. School programs continue to expand as a third integrated preschool class is approved and opens in January. Student enrollment surpasses 200.

2006 - Budget is $8 million and staff reaches 175 as 40th anniversary is celebrated. Fourth integrated class added. Behavioral specialist in autistic spectrum disorders is hired to supervise newly created home based EI services utilizing Applied Behavioral Analysis (ABA).

2007 - 2008 - Home based Preschool ABA services are added in 2007. Hellenos House, our sixth IRA, opens in Wantagh. 5Plus services continue to expand as a weeklong overnight summer camp commences in Garrison, NY, with a second session added the following year.

2009 - Lease of Plainview facility is extended for 5 years. Educational programs continue to expand as school enrollment exceeds State Education Department mandates and ACDS is authorized to serve an additional child in each of our classes.

2010 - We open our seventh IRA on West Loines Ave. in Merrick. Our first supportive residence opens as an apartment extension is added to our Freeport IRA, providing a more independent living arrangement for 2 former residents of ACDS group homes. Day habilitation services are added to the roster of adult services and are housed in a newly purchased facility on Newbridge Road in Levittown. School facility is reconfigured to add a self-contained clinical wing for all therapy services to students. Services to Autistic children expand with addition of ABA classes in EI and preschool, allowing for continuity of services from early childhood through preschool.

2011 - ACDS celebrates it's 45th Anniversary. 300 employees are providing service currently to nearly one thousand individuals. Operating budget reaches $14 million, having more than doubled since the current administration assumed responsibility in 2004. Additional ABA class scheduled to open in September. Services to this population surpass 40 individuals.