We have now entered a fourth wave, or phase, of economic development (ED), according to the model popularized by Leigh and Blakely (2013): sustainable ED, or ED that is sensitive to concerns of the natural environment and also, increasingly, social equity. Personally, I applaud this new phase of the profession, although I have struggled to understand it fully. Apparently, I am not alone:

The broad concept of sustainability has caught the attention of policy makers and citizens the world over. Much of what the term means today is considerably different from what it conveyed a decade ago. As the broad concept of sustainability has evolved, so too have several of its derivatives: sustainable communities, livable communities, and sustainable cities. Even so, these are not concepts that are susceptible to easy or quick definitions. As Beatley and Manning (1997: 3) point out, “there is a general sense that sustainability is a good thing (and that being unsustainable is a bad thing), but will we know it when we see it?”

(Portney 2013: 1) Jepson (2001) details the origins of the term and concept of “sustainability,” beginning in the physical, biological sciences – where some physical scientists believe the concept should remain, exclusively. Clearly, however, sustainability has jumped – imperfectly, perhaps – to the human realms of politics, economics, geography, demography, and ED.