Inclusion Criteria:  Formative phase: For in-depth interviews with HIV CTC staff, eligibility will be employment at an HIV CTC within the three municipalities -Ilala, Temeke and Kinondoni-- that have been selected for this study, within Dar-es-Salaam city. We will purposively select a mix of levels of staff to include both staff who provide direct clinical services (e.g. doctors, nurses) and those who provide support functions and interact directly with clients (e.g. receptionists, guards).  For in-depth interviews with people living with HIV (PLWH) who use drugs, criteria for inclusion are:  current user of drugs self-report of living with HIV age 18 and over (legal age of consent in Tanzania) and ability to provide informed consent.  Intervention pilot testing phase:  -This will include CTC staff and other staff within the medical facility where the CTC is physically housed who come into direct contact with clients attending the CTC (guards, receptionists, lab and pharmacy staff), who work in one of the seven clinics selected for this study.  Exclusion Criteria:  Under the age of 18. Refusal to Consent. PLWH participants who appear to be too impaired to provide informed consent or answer questions accurately will be ineligible.