This paper describes a new project funded by the Brookings Institution Urban Market Initiative. In this project, the Urban Institute and NNIP partners in five cities will use parcel-level data as a basis for developing "decision support tools" to better guide the evolution of local land markets. The project will entail analysis to better understand real estate market potentials for different types of neighborhoods in these cities and the mixes of public actions generally appropriate to each type. The partners will also go further to develop computer-based tools that take advantage of the data to better design and implement specific courses of action in that context.