Presented here is a simple formula to value risky corporate lease payments. When the amount of debt displaced by a lease depends on the value of the lease, the displaced debt tax shields are risky. The value of these risky tax shields is less than the value of riskless tax shields. The valuation of the lease makes use of a dynamic investment strategy that replicates the lease payments and associated tax shields from displaced debt. A useful variation of the valuation formula requires only the contractual cash flows and the yield on lease-equivalent debt. Calculations show that the new formula can produce significantly different lease values from formulas that assume riskless cash flows.