The study will be implemented in two provinces in Vietnam: Phu Tho and Vinh Phuc. A randomized controlled trial will be conducted to evaluate the impact of the intervention in 60 commune health centers. From each center we will recruit 5 Community Health Workers (CHWs), 15 Injecting Drug Users (IDUs), and 10 Family Members (FMs) (totaling 300 CHWs, 900 IDUs, and 600 FMs). The outcomes will be evaluated at 3-, 6-, 9-, and 12- month follow-up assessments. The specific aims of the study are as follows: