Lack of reproducibility of research results has become a major theme in recent years. As we emerge from the COVID-19 pandemic, economic pressures (increasing scrutiny of research funding) and exposed consequences of lack of societal trust in science make addressing reproducibility of urgent importance. TIER2 does so by selecting 3 broad research areas (social, life and computer sciences) and 2 cross-disciplinary stakeholder groups (research publishers and funders) to systematically investigate reproducibility across contexts. The project starts by thoroughly examining the epistemological, social and technical factors (epistemic diversity) which shape the meanings and implications of reproducibility across contexts. Next, we build a state-of-the-art evidence-base on existing reproducibility interventions, tools and practices, identifying key knowledge gaps. Then TIER2 will use (co-creation) techniques of scenario-planning, backcasting and user-centred design to select, prioritise, design/adapt and implement new tools/practices to enhance reproducibility across contexts. Alignment activities ensure tools are EOSC-interoperable, & capacity-building actions with communities (i.e., Reproducibility Networks) will facilitate awareness, skills and community-uptake. Systematic assessment of the efficacy of interventions across contexts will synthesise knowledge on reproducibility gains and savings. A final roadmap for future reproducibility, including policy recommendations is co-created with stakeholders. Thus, TIER2 will significantly boost knowledge on reproducibility, create tools, engage communities, implement interventions and policy across different contexts to increase re-use and overall quality of research results in the European Research Area and global R&I, and consequently increase trust, integrity and efficiency in research.