Inclusion, integration and addressing the needs of marginalised groups, are key priorities for many European countries. CARDET, in collaboration with the Ministry of Education and Culture from Cyprus and partners from 5 EU countries participate in the project iDecide, under the ERASMUS+ KA3 Support for Policy Reform program of the European Commission. The project aims to develop an innovative toolkit, a mobile app, and an induction course to support evidence-based policy making that can lead to the reduction of disparities in learning outcomes and marginalization, by supporting school leaders, school staff, and policymakers to engage in shared and inclusive decision making. By implementing the toolkit and collecting rich data, partners will better understand the complexities of how decisions at school level influence marginalised groups. The project will also develop concrete recommendations for policy and practice on how to engage in shared decision making, giving voice to all stakeholders.