Why do traffic circles work some places and not others?

One day as an undergraduate student in a law and economics class, I listened to my professor tell a simple story about traffic rules in a quaint European town. I’ve forgotten where it was—probably somewhere in Holland—but the gist was that the municipality had gotten rid of all stops signs and traffic lights in the town center, and after the change, travel times and accidents both fell.

Almost a decade later, there are numerous examples of small European towns that did away with signal lights and traffic signs and, voila, traffic began to flow better, transit times decreased, and roadways became less dangerous for pedestrians and vehicle passengers alike. The absence of conventional rules improved outcomes.


In Haiti, there is no meaningful enforcement of any set of traffic rules. Virtually all road space could be called “shared”—pedestrians, motorcycles, and four-wheel vehicles use the same space everywhere; only the largest intersections have traffic lights; there are no crosswalks and almost no stop signs. Instead of following a rulebook, drivers rely on local, informal norms.

Traffic in Port-au-Prince is horrifying. People do not yield to each other and spontaneously fall into an efficient order, as in England’s Poynton. In Haitian transit, people approach shared space as if they’re homesteaders on an Oklahoma land run. It’s every-man-for-himself, where every man is trying to grab every centimeter of available road space before someone else does. Instead of a free-flowing circle, a roundabout becomes an immobile tangle of tap-taps, traffic jams radiating in all directions.

 Insightful. I'd long taken for granted the idea that doing away with traffic lights would encourage both drivers and pedestrians to be more vigilant and aware, leading to fewer accidents, but I had not considered that the context in which that would work required some established norms which don't exist everywhere.


Perceptions of risk and consequent trade-offs might explain other differences between countries. “Differences…between high- and low-income countries are probable,” the authors write, “because there may be differences in the hazardousness in the respective road traffic environments, and how much people choose to focus on such risks when there are other unmet needs such as food, stability and protection against diseases.” They suggest that people in low-income countries may “prioritise urgent needs such as food, water and stability over accidental risks such as road traffic accidents.”