Environmental degradation and pollution, climate change, and the destabilization of the ecosystem biodiversity, damage health and quality of life, and affect socially disadvantaged and vulnerable populations. Negative outcomes can be balanced by positive effects that healthy environments, such as green and blue spaces, can have on human and ecosystem health. Socio-economic costs are significant and public policies could develop preventive actions. HERA will set the priorities for an environment and health research agenda in the EU by adopting a holistic and systemic approach in the face of global environmental changes. Research will support decision-making and help attain the ultimate goal of protecting and improving ecosystem quality and human health. HERA will identify both the environmental opportunities for health improvements and the major environmental problems and challenges. This ambitious objective will only be possible through a close and continuous interaction with numerous and diverse stakeholders in the wider environment and health area. HERA specifically aims: 1) to proactively identify key sectors and policy areas in the field of environment and health that will benefit from additional scientific evidence in the next decade; 2) to develop a European medium-term research and innovation agenda covering key strategic research and policy aspects; 3) to propose strategies and tools to respond to the new and continuing challenges in environment and health nexus, by ensuring the engagement of stakeholders, increasing coordination and cross-fertilisation of ideas, and contributing to the European environment and health process and policy activities. HERA is structured in workpackages addressing policy needs, knowledge gaps, establishment of new guidelines, stakeholder community consultation and establishment of the research agenda. A specific activity focuses on knowledge transfer towards countries with less active research in environment and health.