The seminal contribution by Kiyotaki and Moore (1997) has spurred a vast literature on the importance of collateral constraints in propagating and amplifying shocks to the economy. However, most papers in the literature using collateral constraints assume non-state contingent debt, i.e., markets...

We examine the role of collateral in a dynamic model of optimal credit contracts in which a borrower values both housing and non-housing consumption. The borrower's private information about his income is the only friction. An optimal contract is collateralized when in some state, some portion...