In this article, I examine the current state of knowledge about optimal monetary policy. I distinguish between two literatures, basic and applied. The basic literature is explicit about the frictions that generate a positive value for money and make it socially beneficial. The applied literature...

In this article, I consider environments in which all shocks have finite support and any transfer of resources is ex post voluntary. Consider an allocation that is achievable when potential trading partners know each others' histories. The one-money theorem says that the allocation is achievable...