Therapeutic Communities (TCs) began in the late 1950s as a form of long term residential treatment for substance use disorders. In its beginning stages, TCs were run solely by peers in recovery, and most did not allow program participants to use any medication. However, as decades passed, these communities began to incorporate a more comprehensive approach to recovery by supporting participants receiving medication, and allowing professional staff with substance abuse training to help in the recovery process. Some Therapeutic Communities address other health issues in addition to substance use disorders. Although the first TC was founded in California, today these communities can be found in over 65 countries around the world.