This paper explores how play as an educational tool can enhance social capital for adult learners in institutional settings. Framed by conceptualisations of social capital (Putnam 1993, 2000) and play (Melamed 1987, Meares 2005, Vygotsky 1978) and supported by research literature on play in adult learning, our action research in our adult education classes focuses on cooperative forms of play in which pretend, role-play, improvisation, playful activities and a playful mindset were key components. We investigate these play experiences in terms of their implications for nurturing adult learners' social capital. Our preliminary findings to date reveal that play contributes to social capital by enriching adult learners' engagement, cooperation and sense of connectedness with one another as well as with people, resources and information beyond their group. (Contains 2 figures.)