Rapid urbanization enhances the desirability of policies for preserving open space but those policies may expand the urban boundary and create leapfrog development. We investigate this potential conflict between open space preservation and urban sprawl conceptually and empirically using data from the Baltimore-Washington suburbs. The estimated econometric model indicates that both zoning and forest planting requirements contribute to sprawl by increasing the amount of land needed to accommodate the current number of households. The impacts of these regulations on sprawl are modest, however, increasing urbanized area by less than one percent in response to a one percent increase in any of these three forms of regulation. Thus, while there does seem to be some conflict between open space preservation and prevention of urban sprawl, that conflict does not appear to be acute.