BackgroundHIV prevention is needed among people who use drugs (PWUD) due to mixing sex and drugs, selling/trading sex, and/or injecting drugs. Pre-exposure prophylaxis (PrEP) is an extremely effective biomedical HIV prevention strategy, but uptake remains low among communities most in need of HIV prevention, including PWUD. Previous studies have found that providers are less willing to prescribe PrEP to PWUD, yet PWUD express high levels of PrEP acceptance. More research is needed to understand how people who provide substance use treatment services think about PrEP to maximize this biomedical prevention strategy. MethodsThe study conducted semistructured interviews with 29 staff members in two methadone clinic settings in urban northern New Jersey. Staff members included medical providers, methadone counselors, intake coordinators, front desk staff, lab technicians, security guards, and administrative/leadership personnel. ResultsAll staff recognized the need for HIV prevention among their patient populations, but most were either unaware of PrEP or unfamiliar with its purpose and how it works. Medical providers were more likely to have some PrEP knowledge in comparison to counselors and other staff, but the former largely did not have in-depth knowledge. Among those familiar with PrEP, many confused PrEP with HIV medication, as Truvada was the only FDA-approved PrEP at the time of the study. About half of participants expressed clear support for PrEP, while the other half expressed mixed or negative attitudes related to HIV, sexual behavior, and mistrust of the medication. Both the positive and negative perceptions entailed stigmatizing elements. RecommendationsDue to patients' frequent interactions with non–medical staff (e.g., front desk staff, lab technicians, etc.), all staff, not only medical personnel, should be aware of PrEP and comfortable discussing it to foster well-informed, nonjudgmental conversations about HIV prevention with patients. PrEP education should specifically address HIV and sexual-related stigma, as even positive perceptions of PrEP may entail stigmatizing elements.