This paper presents a model of the land developer's response to the threat of regulatory taking. It shows that the threat of regulation affects development timing and density differently than the regulation imposed with certainty. Planned development proceeds at a more rapid pace under the taking threat, whereas the development density varies systematically by location in a spatial land market. Further, property on which regulations are actually imposed will be developed later than planned when the demanded density is falling over time. Regulated property, however, may be developed even more quickly than planned when the demanded density is rising over time.
