I was having a conversation recently with someone who demanded to know what works. His statement was something like: Come on, Chuck. You’ve studied this stuff for years. You’re the expert. Just tell us what works already.

The question was a little like the annoying old density question—”What is the precise density necessary to create a Strong Town?”—which I’ve been asked for years, and which I long ago addressed in a post. It also danced near an important question of our time: Whose expertise matters? I’ll answer that one quickly.

In a time when society is tasked with efficiently replicating a set pattern of development, the technical professional is the expert. They can live in their hierarchical silo with their narrow but deep expertise and feel confident in simply repeating what they know how to do. That was the case during the time period immediately after World War II, in which American suburbs began to expand at an unprecedented pace. The expert-led approach accomplished what it attempted to do—create rapid growth as a way to keep us from sliding back into economic depression.

In a time when society is tasked with maturing the development pattern, of making increasingly productive use of that which has already been built, the everyday citizen becomes the expert. They are the only ones capable of understanding the fractal minutia of their own place. Technical professionals must evolve to be less like all-knowing rulers and more like humble servants. I’ve written about this extensively as well.

So, the way I would answer the question of “what works” is to start with this sketch of a mature city by the great architect Leon Krier.


The sketch is part of a larger drawing (I’ll share the rest in a moment), but it’s the starting point. Unless your city was founded after 1945, it’s almost certain that you could look at what was there in 1945 and think of that snapshot as the most mature version of your city.

It’s around this point in time that the development of cities shifted from a complex undertaking to one that was merely complicated. To say that in a different way: the building of cities shifted from being a co-creation of the people who lived there to a technical undertaking by professionals. The method of change shifted from a painstaking craft to more of an assembly line. The mature city was assembled incrementally on a continuum of improvement; in contrast, the places we’ve built since about 1945 tend to be built all at once to a finished state.

In a series of presentations on housing that I recently gave, I represented that shift with these slides:

Housing Presentation 1.jpg
Housing Presentation 2.jpg

A cornfield is complicated, but not complex: it requires a lot of technical expertise to maximize yields and account for such things as soil characteristics and weather conditions, but ultimately it’s a monoculture. A rainforest is complex, co-created by countless interactions among thousands of different species that couldn’t possibly be reduced to a formula.

The relationship between a complicated and a complex city is the same: the former is built according to a formula according to technical expertise, the latter incrementally co-created by its inhabitants.

The emphasis in the merely-complicated pattern is on growth. How do we create as much growth as possible, as quickly as possible? The complex pattern experiences growth, but the emphasis is on stability — how do we ensure that, no matter what happens, we’ll still be here tomorrow, next year, and a century from now?

Those administering the complicated pattern — the technical professionals — quickly become obsessed with growth and the inputs (capital) necessary to create accelerating levels of growth. They become trapped in what we’ve called the Growth Ponzi Scheme as liabilities mount over time. Those administering the complex pattern—a co-creation of citizens and humble professionals—obsess over feedback as a way to discern what they should do next. They are seeking stability through the continual harmonizing of many competing objectives, one of which is growth (though not the only one).

This gets us back to Leon Krier. Here are the other two sketches that build from the mature city. The first is the complicated, technically-administered city that has become obsessed with growth. Krier calls this “overexpansion”—the vertical and horizontal simplification of the city to constituents of a growth model. The other Krier sketch he calls “expansion through duplication,” and he even throws in the word “organic,” which I would correlate to “complex.”

leon krier.jpg

The key insight of Krier—and the answer to the question of “what works”—is that the organic city worked. Human habitat, co-created and co-evolved with us over thousands of years, worked. It used feedback loops to harmonize many competing objectives over time.

The question of “what works” is premised on the notion that there exists a pattern of development, or a series of actions, that can be implemented without the struggle of harmonizing competing objectives. That premise is incorrect. Whether we are comfortable with it or not, cities as complex systems require us to work incrementally as a way to obsessively seek out and respond to feedback.

Here’s what I wrote in Chapter 6 of my upcoming book Strong Towns: A Bottom-Up Revolution to Rebuild American Prosperity:

Once we accept the cities are complex systems, we are forced to come to grips with the reality that we can never fully understand them. More to the point, what we often think of as simple and obvious solutions to the problems we face are simple and obvious only because of our limited understanding. The more we truly know, the less clear things become. 

The unfair challenge we face today is that we don’t get to start from that “mature city” in Krier’s first sketch. Almost all of us begin our efforts to build a Strong Town from a state of “vertical and horizontal overexpansion,” a precarious place to be. Instead of giving us a license to bold and decisive action (aka: gambling), these uncharted waters demand that we embrace the underlying complexity, obsess about feedback, and begin the difficult—but rewarding—work of iterating our way back to maturity. That’s what works, and that’s how we build a strong town.