Community Support Systems began in 1962 by a group of individuals concerning the needs and lack of services for children with disabilities. It became incorporated and opened a day school for 12 students ages 6-21. From 1965 to 1970 the school for children with disabilities grew by leaps and bounds. As enrollment rose and the original students were becoming too old for the established programs, the need for additional facilities and programs became apparent. New buildings were rented or purchased including the Activity Center and the Opportunity Center (renovated from an old bowling alley). Additional grants were required for the increased services.

Changes in Illinois law were brewing and children with disabilities under the age of 16 were now being taken into public schools. Many of the older children with disabilities who had received services from the Nanon Wood Achievement School found themselves well prepared for this inclusion process.

In 1970, 40 consumers with disabilities attended programs. However, in 1974 the organization again saw tremendous growth. Many consumers were aging out but even a larger number of younger consumers were enrolling in programs. Consumers who had been with the organization for many years were leaving. By December of 1974 total enrollment had grown to 54.

Programs now included: the Nanon Wood Achievement School, Home Intervention, Developmental Work Activities and the Industrial Sheltered Workshop which provided vocational evaluation, work adjustment training, vocational counseling, personal adjustment training, job-seeking skill development, community job placement and sheltered employment. A decision was made in January 1975 to find a new, larger location. In 1976 the agency purchased and moved into the former Steven's Industries building at 618 West Main in Teutopolis. This building remains the Administrative Offices to this day.

Over the summer of 1980 the school, now named the “Nanon Wood Center for Children’, moved to its new location on Veterans Drive in Effingham. By 1981 the enrollment for the school was at 202 children with disabilities. In the spring of 1984, the agency built its first group home on North Merchant Street in Effingham, known as a Community Residential Alternative (CRA) residence. In 1985, the Board of Directors continued its vision for the future by adding the Supported Employment program. The agency opened the Developmental Training Center in Teutopolis in 1987 and moved the individuals in need of basic developmental training to this new site. Between January 1989 and June 30, 1992, many changes were made. The new Family Matters program was added, another eight-bed group home, the KC House, was opened, parent support groups were started and the “Kids on the Block” educational puppet program was introduced.

In 1991, the agency was renamed ARC Community Support Systems. It was felt that this new name better reflected the diverse population and the wide variety of programs that the organization now offered for all people with disabilities. In 1993, the first annual Golf Tournament was held at the Effingham Country Club and the agency was awarded the Excel Award by the Greater Effingham Chamber of Commerce and Industry. In 1994, Illinois TASH presented ARC Community Support Systems two awards for its community inclusion work and public awareness efforts. By 1998 ARC Community Support Systems had grown to serve 1,043 infants, children and adults with disabilities.

In 1995 the ARC Community Support Systems Foundation, Inc. was created to provide a more stable, long-term financial position to serve the clients of ARC-CSS. In addition to providing this financial base, the Foundation took over the financial aspects, including ownership, of the seven buildings in the ARC-CSS organization.

On September 1, 2000, the Opportunity Center of Southeastern Illinois merged with ARC Community Support Systems. This added 27 full-time employees, as well as a site for work programs and Early Intervention programs to four Illinois counties. In 2004, ARC-CSS built a new 16-bed group home called Oakview. In 2007, they opened the ARC Community Support Systems Counseling Center offering individual, family, couple and group counseling sessions, as well as specialty services to include, court mediation, anger management and Children First services. Also, in 2007, ARC Community Support Systems sold the Opportunity Center in Olney and moved the Children's Programs and Community Employment Services to the newly leased Magura building.

In 50 years, the agency has operated under three Executive Directors: Mike Fortner, Dick Reimers and currently, Mike Poe. Today, the more than 125 member staff, under the guidance of a ten member Board of Directors, annually serves more than 3,100 infants, children and adults with disabilities and their families through advocacy, education, housing, employment and family support programs. Agency staff and management continue to be dedicated to the same ideals that brought the organization together nearly five decades ago…all people with disabilities deserve the same rights, privileges and opportunities afforded to everyone else.

On December 1, 2016 Andy Kistler took over as Executive Director of the agency, replacing the retiring Mike Poe. Kistler had a 20-year tenure with the agency. 

In January of 2016 the Board of Directors made a bold and progressive move changing the name of the agency once again. The new name was simply changed to Community Support Systems, thereby dropping the negative connotation that came with the old acronym "ARC".