Obesity remains one of the most pressing public health challenges in Europe, with substantial health, social, and economic consequences. Despite extensive research and numerous national strategies, obesity prevention efforts remain fragmented across countries, limiting comparability, scalability, and policy impact. The present description introduces the collaborative effort of “OBEClust,” a pan-European initiative designed to harmonize obesity prevention research and policy, fostering collaboration across disciplines, sectors, and countries. OBEClust aims to create a coordinated framework that integrates research methodologies, shared data infrastructures, and knowledge translation approaches to strengthen the evidence base and support the development and implementation of effective and equitable obesity prevention strategies. The initiative brings together researchers, policymakers, and public health stakeholders to standardize core indicators, align evaluation frameworks, and promote evidence-informed policy development. By facilitating cross-country collaboration and reducing duplication of efforts, OBEClust seeks to strengthen capacity for prevention research and accelerate the implementation of effective interventions. Through harmonization and structured knowledge exchange, OBEClust addresses existing gaps between scientific evidence and policy action. This initiative provides a collaborative framework for European obesity research coordination that provides a transferable model for cross-project cooperation through methodological harmonization, structured knowledge exchange, stakeholder engagement, and evidence translation.