There has been a boom in American rail transit construction in the past two decades. That new investment has prompted the question of what planners can do to support rail transit. One popular answer has been transit-oriented development (TOD), increasingly described as a comprehensive strategy for rail-based land-use planning throughout an urban area. This is most clearly illustrated by Bernick and Cervero’s (1997) description of how such projects can link together to create “transit metropolises” where rail is a viable transportation option for many of the region’s residents. In addition, TOD provides an opportunity to examine the regulatory issues discussed in chapter 6, both because it is an explicit attempt to use urban design as transportation policy and because the intergovernmental issues are especially stark in relation to these developments. Having discussed how travelers behave in the first part of this book, we now ask what we know about how cities behave. Stated in general form, the question is rather broad. It concerns the process by which cities and other land-use authorities decide where to put streets, how to structure the local hierarchy of streets, when to develop more or less densely, how to position employment centers relative to residential areas, and so on. Still, the feasibility of land-use plans with transportation goals depends critically on how such authorities behave. Any discussion of the effectiveness of these strategies must address both how communities plan for transportation and how travelers respond to those plans. The primary transportation goal of TOD generally, as currently practiced, is to coordinate land-use policies to support rail transit. In particular, focusing both residential and commercial development near rail transit stations is aimed at increasing rail ridership (e.g., Bernick, 1990; Bernick and Hall, 1990; Calthorpe, 1993; Cervero, 1993; Bernick and Cervero, 1997). Some evidence suggests that residents near rail transit stations are two to five times more likely to commute by rail when compared with persons living elsewhere in the same urban area (Pushkarev and Zupan, 1977; Bernick and Carroll, 1991; Cervero, 1994d).