Problematic psycho-active substance use is highly prevalent in patients consulting in primary care.Although the use of substances is not always problematic, screening for problematic use is justified in the adolescent, adult and geriatric populations, considering the high prevalence, the existence of simple valid screening instruments and cost-effective intervenions. Screening can be performed by simple questions or with standardized questionnaires. When screening is positive, primary care physicians can promote health behaviour changes using brief interventions based on the 5 A's framework. Physicians play an important role in providing immediate and long term caretopatient ssuffering from addiction, if needed in interdisciplinary collaboration.