Harm reduction is a pragmatic approach to reducing the harmful consequences of alcohol and drug use or other high-risk activities, including a variety of strategies, ranging from safer use to controlled use and abstinence. The primary goal of most harm reduction approaches is not to deny or condemn harmful behaviors by individuals, but to work with the individual or community to minimize the harmful effects of a particular behavior. The present review addresses some of the most recent developments related to harm reduction policy, prevention and treatment programs. This review aims to increase public awareness by presenting some of the current information and developments on harm reduction as a tertiary preventive mental health service for substance use disorders that concern all health professionals, especially psychiatrists, general practitioners, family medicine specialists, psychologists, social workers and nurses working in the field of dependence.