Abstract
As an ever-increasing proportion of the world population lives in urban areas, one of the most important equity and social justice challenges governments and public administrations face is urban land-use and transportation issues. Within the context of this challenge, social justice, land use, transportation, health, and environmental dimensions are presented here as "a bundle of tangled elements sensitive to design." The types of interdependence between these different dimensions are then described in more detail and further characterized as part of a sequential-type interdependence. Using notions coming from New Institutional Economics, different modes of governance are examined, and it is found that hierarchy, as opposed to market, is the mode of governance best suited to the task of achieving a more equitable and sustainable urban life. Within this context of the hierarchical mode of governance, professional public administration will be called upon to play a more active role than it has played until now.