["British Journal of Educational Technology, Volume 57, Issue 3, Page 797-821, May 2026. ", "\nAbstract\n\nThis paper focuses on the opportunities and challenges of conducting implementation research when co‐design is central to the project being implemented. A participatory co‐design methodology is proposed to evaluate the co‐design and implementation aspects of a teacher professional development course. The project aim was to co‐create evidence about the effectiveness of Co‐designed, Massive, Open, Online Collaborations (CoMOOCs)—an educational innovation developed with teachers in conflict and crisis settings. CoMOOCs are distinctive through their focus on co‐design with local educators, and on supporting collaborative online, blended and offline spaces for teachers to jointly develop their knowledge and solutions. CoMOOCs have been developed with teachers in two Low‐ and Middle‐Income countries (LMICs): originally with refugee communities in Lebanon, and more recently with migrant and refugee education groups on the Thai–Myanmar border. With funding from the Foreign, Commonwealth and Development Office (FCDO), as part of the Education Research in Conflict and Protracted Crisis (ERICC) programme, we are undertaking implementation research to create a robust body of evidence around which aspects of CoMOOCs are effective, for whom they work, why they work and what adaptations to the model are required. Our Co‐Design Theory of Change embeds implementation research at the heart of the iterative design—implementation—evaluation cycle. This approach combines the methodologies of a design‐based research (DBR) cycle with the methods of implementation research, supported by the following principles: engage collaborators in co‐creating the design, carrying out the implementation and deciding on the evidence needed for effective evaluation; employ a capacity bridging, citizen science methodology to develop and certify the research skills of teachers; collaborate with local partners to undertake evidence curation; and establish local ownership of the interventions to ensure sustainability. In this paper, we present early findings from the implementation research, specifically demonstrating how co‐designing the educational innovation is a vital step to scaffolding successful initiatives.\n\n\n\n\nPractitioner notes\nWhat is already known about this topic\n\nImplementation research is crucial for assessing educational technology innovations for acceptability, adoption, appropriateness, feasibility, fidelity, cost, coverage and sustainability.\nA key principle of implementation research is the intimate involvement of stakeholders in all phases of research, not just dissemination.\n\nWhat this paper adds\n\nThis paper uniquely demonstrates the significant value of a ‘collaboration for co‐design’ approach in a technology‐based teacher professional development (TPD) innovation, ensuring the sustained involvement of local education providers.\nFindings from Phase 1 of this implementation study show that co‐design fosters crucial value for implementation by (1) enabling sharing across contexts and building solidarity and collective agency among teachers facing similar global challenges; (2) enhancing practical application and adaptation of locally embedded knowledge, thereby directly contributing to appropriateness and acceptability; (3) cultivating a strong sense of ownership among participants through their sustained involvement; and (4) recognising and valuing all participants' knowledge and perspectives, which significantly aids adoption and sustainability.\nFurthermore, the co‐design process directly addresses barriers to digital access by informing the necessity of designing for diverse, flexible modalities (eg, online, blended, and offline formats), ensuring fidelity to the model despite varied engagement methods and enhancing feasibility and coverage from the outset.\n\nImplications for practice and/or policy\n\nFor practitioners developing educational technology interventions in conflict and crisis settings, embedding a ‘collaboration for co‐design’ approach ensures interventions are relevant, acceptable and feasible for local communities.\nThis requires actively engaging local educators in all stages of design, research and implementation to foster ownership and adapt to specific contextual needs.\nFor policymakers and organisations, their support for ‘capacity bridging’ initiatives like citizen social science will empower local teachers to participate in and lead research, thereby generating context‐specific evidence and fostering sustainable knowledge exchange and localised implementation capacity.\nAdvocacy is crucial to end internet restrictions for educational purposes in refugee settings, as reliable internet access is a necessity for learning and professional development and critical for equitable implementation.\n\n\n\n\n"]