Launching of a New Currency in a Simple Random Matching Model

This paper studies the launching of a new fiat currency within a search-theoretic framework. We show that legal tender laws may not be sufficient to guarantee the acceptability of the new currency, and that the withdrawal of a large fraction of the competing currency is essential to avoid the failure of such a launching. The possibility of converting the old currency into the new one can ease the transition to the new currency only if it is combined with strict legal tender laws. Finally, a network externality is identified that may generate inefficiencies in the conversion decision.