We view sustainability as a requirement that welfare should not be expected to decline over time. We impose this requirement as a prior constraint on the consumption-savings-investment problem, and study its implications for saving, risky investment, and the social discount rate. The constraint...

This paper studies the restrictions on consumption, portfolio choice, and social discounting implied by a sustainability constraint, that utility should not be expected to decline over time, in an economy with risky investment opportunities. The sustainability constraint does not distort...

We investigate whether a model with time-varying probability of economic disaster can explain prices of collateralized debt obligations. We focus on senior tranches of the CDX, an index of credit default swaps on investment grade firms. These assets do not incur losses until a large fraction of...