A list of four substance use treatment clinics and four HTC/healthcare clinics, which have been identified and approved by the City of Cape Town, South Africa will be randomized to begin the intervention during one of the four cycles. Each HTC/healthcare clinic will be paired with a substance rehab center based on geographic proximity, and each pair was randomized by computer into four succeeding 6-month implementation cycles where implementation of the WHC is taking place simultaneously at the paired sites. Up to 120 HIV positive participants will be recruited in each cycle (60 from each clinic) for the patient level outcomes.