Funding for mental health research in Europe is much lower than the population impact of these disorders with spending being less than half the disability burden. This is despite mental health research providing a similar investment return to other health areas. ROAMER (ROAdmap for MEntal health and Well-being Research in Europe) developed a comprehensive and integrated mental health research roadmap, focused on improving the mental health of the population. ROAMER analysed existing complementary resources among European regions, and involved input from over 1000 individuals and stakeholder organisations. Recommendations were prioritised through iterative feedback, consensus meetings, international advisory boards and surveys of researchers, experts and wider stakeholders in Europe. Six prioritised questions were produced: these are targeted, actionable, built on excellent European science and resolvable in the next 5 to 10 years. The answers to these proposed research questions will improve the mental health of European citizens and tackle societal challenges.