Our central concern in this paper is to examine some alternative policies for physically containing the growth of urban areas. We undertake a microsimulation to provide a comparison between land use planning policies that enforce an urban growth boundary and policies that limit development at the periphery using taxes. We parameterise our microsimulation using the structure of demand and policy implemented in a rapidly growing city in the south of England. We make no judgment as to the optimality or otherwise of the existing degree of constraint: we take that as datum and analyse only the welfare costs, distributional impacts and effects on urban densities of alternative ways of achieving the currently observed degree of constraint. The methodology we deploy to address these issues could be turned to a wide range of other urban modeling purposes. It has the advantage of being clearly founded in microeconomic theory and applies observed behavioural relationships, estimated from the relevant economic data. We find that the use of a tax on land could produce the same limitation on growth as existing regulatory policies but provide higher equilibrium welfare levels. We find that the use of a tax on transport costs, however, while capable of producing a compact urban form, would not raise welfare when compared with regulatory approaches.