The objective of the study is to assess the practice and quality of community-based and community-led communicable diseases (Human Immunodeficiency Virus (HIV), viral hepatitis, sexually transmissible and – where relevant – tuberculosis) testing and linkage to care services for People Who Use Drugs (PWUD) in Europe. For the study, focus groups were developed and prepared with people who use drugs and are at risk from HIV and / or viral hepatitis in the countries of the four Lighthouse Project implementations (Belgium, Czechia, Finland, and Italy).