Research Summary: To further our understanding of how and why organizations engage in coopetition, we explore cooperative and competitive actions in the craft beer industry. Through an inductive field study, including interviews with craft brewery owners, we propose collective identity and collective norms play a critical role in the persistence of coopetition over time. Our process model suggests that (a) an oppositional collective identity, (b) the shared belief that a rising tide lifts all boats, and (c) the shared belief that advice and assistance should be paid forward, can lead to the persistence of coopetition beyond market category emergence. Managerial Summary: This paper develops a theory of how smaller, craft-based organizations (i.e., "Davids") encourage cohesion and cooperation amongst themselves when operating against an incumbent market of massproducers (i.e., "Goliaths"). An ideological opposition to existing players can lead to a shared belief that helping organizations like your own benefits everyone-the rising tide lifts all boats mentality. Similarly, when organizations first enter a market and receive help from established members, they can feel compelled to help others who enter the market after-the pay-it-forward mentality. Together, these mechanisms offer an explanation as to how and why coopetition might persist in a market category over time. K E Y W O R D S coopetition, market categories, oppositional identity, qualitative research, reciprocity