This report seeks to better understand the prevalence of poor mental health for different population groups, identify time trends and map barriers to accessing services. It also investigates policy measures directed towards mental health services, and actions taken in other environments (importantly, schools and workplaces) to prevent or address poor mental health. In this report, Eurofound brings together evidence from the literature, EU-level surveys, expert reviews and national administrative and survey data collected by the Network of Eurofound Correspondents and through desk research.