The mechanism-design approach to monetary theory is the search for fruitful settings in which money is necessary for the achievement of some desirable allocations. Fruitfulness means that the settings provide insights about puzzling observations and policy questions. Settings with three...

Monetary policy and the welfare cost of inflation cannot be studied without some specification of allowable fiscal instruments. Here, feasible policies are implied by the frictions imposed to get roles for money and credit. The model has extreme versions of an above-ground economy - people who...