Since 1969, Cornerstone Services has been an advocate and provider of residential, behavioral health, training, employment, and other services for people with disabilities in the Will County, Ill. area. The agency is a recognized leader in providing community-based support services that enhance independence. Cornerstone is fully licensed by local, state, and federal agencies and is accredited by CARF . . . The Rehabilitation Accreditation Commission. The agency accepts Medicaid and private insurance.