You are here!  Chances are you're curious about (or even already registered for) the seminar that I'll be offering during 2013 IAP @ MIT:

Keystone Cities: Networked Approaches to Urban Sustainability

Keystone Cities is going to be a dynamic and interactive exploration of how the definition of "urban sustainability" has evolved over the past two decades (give or take a few years).  

It used to be a "green" municipal government could get by putting in LED traffic lights and turning off the A/C in City Hall an hour early. Not anymore.

Why "Keystone" ?

The name for the seminar refers to the new role played by municipal governments that are  pursuing ambitious sustainability policies.

A keystone is the angled piece of masonry that you find at the apex of a stone archway.  It holds all the other pieces of the arch together so that collectively they can bear the weight of the structure above them.

In some ways, that is a decent metaphor for the current role of municipal governments: Not bearing the full weight of urban sustainability policies, but establishing a network of multiple actors (the arch) that makes it possible for a much bigger project to be built than any one actor could accomplish on their own.

I said "a decent metaphor", but not a perfect one.