Despite the progress in effective treatments for HIV, viral hepatitis, tuberculosis and sexually transmitted infections (STIs), these infections remain major public health concerns across Europe. Recurring challenges of late presentation and unprioritized prevention programmes need to be effectively addressed in order to control and prevent transmission and ensure that people are diagnosed early and rapidly enter the care system. The prevalence of co-infections is high due to the social context of key populations and the shared modes of transmission, varying with local epidemiology, which underlines the need to combine efforts throughout the continuum of care.