The proposed study will investigate the knowledge level, attitudes, and perceptions among staff of Methadone Maintenance Treatment (MMT) clinics and intravenous drug users (IDUs) who attending MMT clinics, which is the most reachable population for HCV/HIV intervention in China. This study will also explore the barriers that prevent IDUs from getting HCV/HIV intervention/prevention and medical care services. This study will help to understand and address this important problem in China and other Asian countries.

The investigators propose to conduct 3 inter-related studies over 4 years using both qualitative and quantitative research methods to address a series of research questions. Firstly, The investigators will begin by assessing HCV/HIV knowledge, attitudes, perceptions, risk behaviors, and infection among IDUs in MMT clinics (Study 1) and HCV/HIV knowledge, attitudes, and HCV/HIV-related services among MMT staff (Study 2). Secondly, based on knowledge accumulated from Studies 1 & 2; The investigators will adapt and develop HCV/HIV education materials appropriate for Chinese IDUs and drug treatment service providers, and then use the Transtheoretical Model of Behavior Change as a conceptual model to measure if our educational program will increase patients' readiness to consider changing HCV/HIV risk behaviors and getting medical care for HCV/HIV (Study 3). Finally, by integrating findings of these three studies and by consulting with leading experts in HCV/HIV. The investigators plan to develop HCV/HIV intervention program applicable in China, which can be tested in future formal experimental trials.

Inclusion Criteria:

• several failed attempts to quit the use of heroin
• at least two terms in a detoxification center
• age at least 20 years
• being a registered local resident of the area in which the clinic is located
• being of good civil character

Exclusion Criteria:

• there is no exclusion criteria