Information technologies can help planners improve the efficiency of metropolitan governments and markets, explore the nature of spatial interactions, and understand the composition and workings of communities. IT itself also serves as a significant stimulus for change, since it can affect the spatial relationships that shape our urban fabric. This raises a complex and interesting set of issues:

• Will dense urban centers still be needed, as IT and telecommunications make time/place separation a less serious problem than in the past?
• Can-and should-technology be used to manage the proliferation of urban sprawl?
• Will technology facilitate further polarization of society and heighten the redlining of the poor and other minorities?
• Is it possible to translate improved understanding of environmental impacts (such as air, water, and land pollution) into useful land use management and control structures?
• Can technology help fill the gap between elegant but quickly outdated comprehensive master plans on the one hand, and site-by-site reviews on the other, which are forced to use unclear or constantly changing yardsticks for pacing growth, protecting environmental resources, and mitigating the marginal impacts of development?

To address these questions, the Planning Support Systems group has focused on three primary lines of inquiry to date.

• First is the development of appropriate information infrastructures for handling digital spatial data. These infrastructures, in combination with networks and the World Wide Web, provide planners with easy, structured access to vast stores of online information, along with the tools for analysis and visualization that are needed to aggregate, manipulate, and recombine this information appropriately.
• The second focus is on understanding urban spatial structure and modeling urban futures. This work involves using information technology to shed light on the relationships among land use, transportation, jobs accessibility, and community development.
• The third area of study examines how IT and the Web can be used together to improve citizen access to planning-related debate and to better inform constituents about planning issues, through the use of representations aids that help in visualizing and debating urban futures.

As IT evolves and as our understanding of its planning implications improves, PSS research is beginning to shed light on the broader set of issues outlined above. We believe that the pathway toward answering such questions involves a mix of hands-on experience and informed reflection that draws upon the best of what MIT has to offer.