How do markets that address grand challenges emerge and grow? Many studies emphasize social movements as key contributors to such market formation efforts, while others privilege entrepreneurs, diversifying entrants, or the state. While these and other conditions constitute important pieces to the market formation ‘puzzle,’ little is known about how the pieces fit together. In this study, we treat market formation as a configurational phenomenon that rests on collective action by heterogeneous actors in diverse contexts. Using fuzzy-set Qualitative Comparative Analysis, we identify three distinct paths to high adoption of solar photovoltaics across different European countries, each relying on a different combination of conditions. We discuss contributions to research on social movements and markets, and to the broader literature on collective action and market formation.