ICL provides mental health treatment services throughout Brooklyn to people of all ages. The agency's 5 New York State Office of Mental Health-licensed clinics offer individual, group and family therapy; psychiatric assessment; medication management and education; crisis services; psychological testing and much more. Three of ICL's clinics are operated by its subsidiary, ICL Guidance Center of Brooklyn.

ICL also offers clinical treatment through its Continuing Day Treatment program and Assertive Community Treatment teams.