This document is the work of UNODC and WHO to support Member States in their efforts to develop and expand effective, evidence-based and ethical treatment for drug use disorders. The Standards are intended for all those involved in the policy development, planning, funding, delivery, monitoring and evaluation of treatment services and interventions for drug use disorders. This document is based on currently available scientific evidence on treatment for drug use disorders and sets out a framework for the implementation of the Standards, in line with principles of public health care. The Standards identify major components and features of effective systems for the treatment of drug use disorders. They describe treatment modalities and interventions to match the needs of people at different stages and severities of drug use disorders, in a manner consistent with the treatment of any chronic disease or health condition.