This paper analyzes monetary exchange in a search model allowing for multilateral matches to be formed, according to a standard urn-ball process. We consider three physical environments: indivisible goods and money, divisible goods and indivisible money, and divisible goods and money. We compare the results with Kiyotaki and Wright (1993), Trejos and Wright (1995), and Lagos and Wright (2005) respectively. We …nd that the multilateral matching setting generates very simple and intuitive equilibrium allocations that are similar to those in the other papers, but which have important di¤erences. In particular, sur- plus maximization can be achieved in this setting, in equilibrium, with a positive money supply. Moreover, with ‡exible prices and directed search, the …rst best allocation can be attained through price posting or through auctions with lotteries, but not through auctions without lotteries. Finally, analysis of the case of divisible goods and money can be performed without the assumption of large families (as in Shi (1997)) or the day and night structure of Lagos and Wright (2005)
