Food security depends on farming and on how food materials become available for processing and marketing. The practice of collecting food materials, or bulking, links farmers, traders and processors. The research aims to understand how and why such a multifaceted practice, involving coordination between actors, becomes institutionally viable. Case-studies of bulking advance an interdisciplinary understanding of governance. A comparative approach unravels how bulking is embedded in social networks and institutions. A longitudinal perspective reveals how bulking practices stay intact despite external pressures. The institutional perspective has relevance for development practice and policy targeting interventions to collective marketing and value chains.