Manual for use in primary care. There is substantial evidence for the benefits of screening and brief intervention in primary health care for alcohol problems. However, there is a need for screening and brief interventions with cross-cultural relevance for substances other than alcohol or tobacco, such as cannabis, amphetamines, cocaine and opiates. The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) was developed for the World Health Organization (WHO) by an international group of substance abuse researchers to detect and manage substance use and related problems in primary and general medical care settings. Primary health care professionals are well-positioned to provide interventions targeted to all substances irrespective of their legal status. The ASSIST screening test version 3.0 is available in English and in 10 other languages (Arabic, Chinese, Farsi, French, German, Hindi, Portugüse, Russian, Spanish and Ukrainian).