Encounters with private security guards among people who inject drugs in a Canadian setting

• We examined encounters with security guards among people who inject drugs (PWID).
• Over one third of PWID reported having at least one encounter with a security guard.
• Security guard encounters often involved physical and verbal abuse.
• Various markers of vulnerability and harm were associated with security guard encounters.
• The findings suggest a need for structural interventions to reduce harm among PWID.