Intensive Outpatient (IOP) Substance Abuse treatment is designed for clients who have severe substance abuse needs due to ongoing substance use, or are released from an inpatient treatment setting. IOP groups will run for 12 weeks, and clients will participate in three, three hour groups per week. Group therapy sessions will consist of psycho-education, as well as therapeutic process. This will provide clients the opportunity to learn new skills, explore their historical pattern of substance use, and receive feedback from peers. This group will utilize the Matrix Model for Criminal Justice Settings, developed by Donna Johnson, Richard Dawson, and Jeanne Obert. Once the client has completed 12 weeks of IOP, they will step down to weekly outpatient substance abuse group therapy. For a client to complete treatment successfully, they will have to complete 12 weeks of IOP as well as a minimum of six additional months of weekly outpatient therapy.