What drives businesses to transact with complementary currencies?

There is an ongoing debate on complementary currencies' (CCs) contribution to a transition towards resilient and sustainable economies. As part of this debate, this paper investigates which factors lead to significant acceptance and sufficient growth of a CC from a bottom -up perspective, i.e., based on its members' decisions. First, we identify the benefits and costs driving firms' use of CCs and find four factors that constitute a trade-off: credit gains, reciprocity expectations, coordination costs, and intrinsic motivations. Second, we use an agentbased model to explore how these elements determine CCs' success as a network. Our key finding is that the coupling of intrinsic motivation with preferential attachment - a phenomenon where members are more likely to transact with each other rather than with outsiders - may be the key to growth and acceptance: these results suggest that intrinsic motivation provides an incentive to join the network, but preferential attachment is the emerging economic rationale that drives firms' acceptance of CCs. The identified trade-off and the theory of intrinsic motivation -preferential attachment provide new avenues to investigate under what conditions CCs contribute to resilient economies.