In this lecture, I explain what the microfoundations of money are about and why they are necessary for monetary economics. Then, I review recent developments of a particular microfoundation of money, commonly known as the search theory of money. Finally, I outline some unresolved issues.

We study general equilibrium with nonconvexities. In these economies there exist sunspot equilibria without the usual assumptions needed in convex economies, and they have good welfare properties. Moreover, in these equilibria, agents act as if they have quasi-linear utility. Hence wealth...

We use a modified version of the Lagos-Wright model to introduce an essential role for banks. Due to preference shocks, agents have excess demand for or supply of money balances. Banks arise to reallocate excess cash by taking deposits from sellers and making loans to buyers. We consider two...

This paper advances a model which can account for these five prominent facts of monetary economics. (i) Money is held in non trivial amounts even though it is a dominated asset. (ii) High rates of inflation lead to low rates of growth. (iii) Monetary injections momentarily depress the rate of...

We consider an economy where trade is decentralized and agents have incomplete information with respect to the value of money. Agents' learning evolves from private experiences and we explore how the formation of prices interacts with learning. We show that multiple equilibria arise, and...