 The study aimed to understand why unvaccinated adults who inject drugs decline SARS-CoV-2 vaccines and how barriers to vaccination can be addressed. The results showed that participants feared the long-term effects of substance use on their health had mistrust in the medical community and were ambivalent about the value of vaccination. However, the desire to protect loved ones emerged as a key facilitator of vaccination. Community developed messages emphasizing the importance of vaccination and its ability to prevent unintentionally infecting loved ones may help increase uptake among this population. This article was authored by Ian David Aronson, Alex S. Bennett, Marie-André Arduin-Garrière, and others.