The ENGAGEgreen Policy Engagement Toolkit provides practical how-to guidance on connecting research with policy. It is designed for anyone involved in or interested in science-policy dialogue — including researchers, research managers, and organisations working at the science-policy interface. This toolkit was collaboratively developed as part of the Erasmus+ project ‘Enhancing Institutional Capacities and Researchers’ Competencies for Policy Engagement for Green and Digital Transitions’ (ENGAGEgreen), conducted across five European countries. The project brought together Goethe University Frankfurt, Johannes Gutenberg University Mainz, and Technical University of Darmstadt from Germany; BETA Technological Centre at the University of Vic and the University of Granada from Spain; Université Lumière Lyon 2 from France; Ca’ Foscari University of Venice from Italy; and Palacký University Olomouc from Czechia.