I model speculative development races when the time at which the devel
opment effort becomes profitable is uncertain. I first treat the decis
ion of a speculator who has exclusive rights to the development prize.
I then show that development races intensify development effort compa
red with the collectively optimal level of effort. Development races w
ith identical speculative developers reduce aggregate profits and brin
g forward development time, whether or not joint development externali
ties are present. In such races, land use policies that restrict the n
umber of permitted developers can enhance collective returns. (C) 1997
Academic Press.