This chapter outlines and contextualises the development and application of a co-creation toolbox to support transdisciplinary research in affordable and sustainable housing within the RE-DWELL project. Early-stage researchers (ESRs) engaged in an iterative process of designing, testing, and refining tools—including cards, boards, and narrative frameworks—across collaborative events in Helsinki, Reading, Delft, and Barcelona. These tools operationalise systems, target, and transformation knowledge, facilitating engagement among academic and non-academic stakeholders, including community members, policymakers, practitioners, and industry representatives. Local implementations in Lisbon, London, and Nicosia illustrate how context-sensitive adaptations of the toolbox supported co-creation, dialogue, and strategic problem-solving in real-world housing initiatives. Through this process, ESRs strengthened transdisciplinary competences, including systems thinking, anticipatory and normative reasoning, strategic planning, and interpersonal skills. The findings indicate that participatory tools function as adaptable scaffolds for collaborative knowledge production, supporting inclusive decision-making, mutual learning, and the generation of actionable outcomes that contribute to sustainable, socially responsive, and contextually grounded housing solutions.

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