Chestnut Health Systems (Chestnut) is a private, not-for-profit 501(c)(3) charitable organization governed by a volunteer Board of Directors.

Chestnut offers a comprehensive scope of behavioral health and human services in Illinois, U.S.A. Our professional and experienced staff is committed to providing high quality care and services to the communities we serve. From drug and alcohol addiction treatment facilities (residential and outpatient), to work-life and employee assistance programs, to a research institute, Chestnut continuously works to achieve its mission to make a difference and improve quality of life through excellence in service.

Chestnut is comprised of the following five core service areas:

• Chemical dependency treatment and prevention
• Mental health treatment and housing for persons with mental illness
• Applied behavioral research, training and publications
• Employee assistance and workplace services
• Primary care treatment and preventative services

Chestnut has been continuously accredited by The Joint Commission (JCAHO) since 1975.