The purpose of this study is to evaluate the effects of a brief motivational intervention in reducing risky injection practices among injecting drug users (IDUs). The investigators hypothesis is that motivational intervention will be more effective than educational intervention in reducing risky injection practices among IDUs.

Injecting drug users (IDUs) are among the most vulnerable populations at risk to contract human immunodeficiency virus (HIV) and hepatitis C virus (HCV). Among Canadian cities, Montreal holds one of the higher HIV and HCV contraction rates in the IDU population. Results from SurvUDI, a population survey among IDUs conducted in the province of Quebec (Canada), show that in Montreal 18% of IDUs are infected with HIV and 67% are infected with HCV. The cornerstone of HIV and HCV prevention strategies is to give information on safe injection practices and to make available sterile syringes and other injection equipment. However, the SurvUDI survey reveals that a large proportion of IDUs recruited in community programs offering sterile injection equipment and information on safe injection practices are still sharing needles with other IDUs. Indeed, it seems that information dissemination and distribution of sterile injection equipment are not sufficient in order to control the HIV and HCV epidemic among IDUs. As a matter of fact, it is obvious that complementary interventions such as behavioural interventions are required. Motivational interviewing is an intervention technique centered on the individual. It aims to enhance intrinsic motivation to change behavior by helping the individual to resolve ambivalence. The scientific literature indicates that brief motivational intervention is a significantly effective intervention in order to reduce drug use problems and other related health problems. Furthermore, motivational intervention is well adapted for IDUs' resistance to change and their difficulties related with involvement in long-term therapeutic process. The present study's hypothesis is that IDUs assigned to the experimental group (brief motivational intervention) will present a greater diminution of their risky injection practices in comparison with IDUs assigned to the control group (educational intervention).

Inclusion Criteria:

• In the last month, at least one cocaine injection
• In the last month, at least one injection with a syringe or another piece of injection equipment that has been used by someone else
• 16 years old or more
• French speaking
• Being able to give informed consent