Services delivered via outreach have been an integral and well-established approach to reach, engage, and support people who use drugs for several decades. The need for outreach programs heightened during the Coronavirus Disease 2019 (COVID-19) pandemic and ongoing drug poisoning crisis with reduced access to fixed sites and increased contamination of the drug supply. This document is intended to provide an overview of outreach programs for people who use drugs. It summarizes the published and grey literature on the effectiveness of different outreach programs. It also summarizes examples and lessons from the Ontario context discussed at a lunch and learn event. Across the literature, there is a lack of consensus on a definition of “outreach” programs, with great variation of how this approach is designed, implemented, and evaluated. For the purpose of this document, we consider some key characteristics of outreach programs to include those that:

• Are delivered by people with living/lived experience, volunteers, or other workers;
• Reach and engage with people who cannot, do not, or are less likely to be accessing or using services at a fixed site;
• Address barriers to access by taking information, supplies, services, referrals, and resources to people;
• Focus on reaching and engaging with people or groups of people rather than organizations;
• Occur in locations where people live or spend time in communities;
• Can have varied services linked with outreach.