Is accessibility an idea whose time has finally come?

The idea that accessibility is the true goal for transportation planning goes back many decades, starting with notable writings in the 1950s, followed by a flurry of writings in the 1970s. Since then considerable academic work has gone into the development of accessibility measures, but their use in transportation planning is not yet pervasive. In this essay, I reflect on why progress toward the wholesale adoption of an accessibility-oriented approach in planning practice has been slow, review some of the promising efforts in recent years that suggest that transportation planning may be on the cusp of an accessibility era, and offer thoughts about the power of the accessibility concept as a framework for thinking about the urban environment.