The recent crisis was characterized by massive illiquidity. This paper reviews what we know and don't know about illiquidity and all its friends: market freezes, fire sales, contagion, and ultimately insolvencies and bailouts. It first explains why liquidity cannot easily be apprehended through...

In the data, a sizable fraction of price changes are temporary price reductions referred to as sales. Existing models include no role for sales. Hence, when confronted with data in which a large fraction of price changes are sales related, the models must either exclude sales from the data or...

We develop a two-stage game in which competing airlines first choose the networks of markets to serve in the first stage before competing in price in the second stage. Spillovers in entry decisions across markets are allowed, which accrue on the demand, marginal cost, and fixed cost sides. We...