Home Treatment (HT) has been successfully implemented in adult psychiatry in several countries including Switzerland. Patients with addiction problems were generally excluded even if the latter was not the main diagnosis. On the other hand, community treatments have successfully been established for these individuals. The investigators have recently offered HT to persons with severe addictive disorders which was well accepted.

The investigators intend to conduct a pilot study to prepare a large-scale study if successful. The investigators intend to compare HT to treatment as usual (regular inpatient treatment) on a specialized ward with respect to readmission rates during 6 months after discharge. The data show that 70.8% of all readmissions occur during the first 6 months. Therefore, a period of 6 months is considered an adequate time interval to sufficiently answer this pilot study's question.

Inclusion Criteria:

• Substance use disorder
• age 18 or above
• sufficient french language skills
• competent subjects
• consent to randomization progress

Exclusion Criteria:

• organic brain disease or developmental disorder
• non voluntary admission
• severe somatic comorbidity
• History of complicated substance withdrawal
• acute suicidal ideation
• aggressive behavior
• acute psychiatric disease such as mania or psychosis
• distance to center (must be reachable within 60 minutes)