The literature on prefiguration offers limited theoretical and empirical clarity, particularly regarding its potential as a tool for transformative change. While existing studies describe prefigurative practices in social movements (Maeckelbergh, 2009) and affirm their theoretical relevance (Yates, 2015), less is known about how prefiguration can function within research aiming for systemic change. This paper advocates for a more structured understanding of prefiguration within transdisciplinary action research, focusing on its ethical stance and the dynamic learning processes it enables in alternative social organisations. It highlights two underexplored processes: (1) emergent learning within and beyond prefigurative practices, and (2) the diffusion or “scaling” of these learnings to broader contexts (Hermans et al., 2016). Drawing on urban living lab research (van Oers et al., 2024), the paper conceptualises prefiguration as constituent experimentation. Using urban food initiatives from the SURFIT project it illustrates how collaborative experimentation can drive systemic transformation. By integrating insights from sustainability transitions, social learning, and urban living labs, the paper proposes “experimental prefiguration” as a framework for embedding grassroots innovations into cycles of co-design, reflexive learning, and multi-scalar scaling, while acknowledging the challenges involved.