100 Years ago, Zoning Changed how US Cities Grow. Today, it is Ripe for Reform.

Euclidean zoning was enshrined in U.S. town planning by a 1926 Supreme Court decision. Cities are recognizing it’s time for some drastic changes.

2 minute read

February 20, 2026, 6:00 AM PST

By Diana Ionescu @aworkoffiction


Zoning map of Los Angeles neighborhood created by WPA.

A WPA zoning map of Los Angeles from 1933-1939. | City of Los Angeles. Department of City Planning, Public domain, via Wikimedia Commons / Shutterstock

In a piece for Bloomberg CityLab, Anthony Flint describes the rise of Euclidean zoning in the United States, which kicked off with a key 1926 Supreme Court decision that enshrined the separation of uses in U.S. city planning.

“In Village of Euclid v. Ambler Realty Co., a suburb just east of Cleveland barred a real estate company from using their land for industrial use; the developers sued and brought it all the way to the nation’s highest court, which affirmed that municipalities could impose zoning to organize development, as a police power.” The decision led to a new template for the built environment that set a course for modern-day suburban sprawl.

Today, cities and states are reassessing the usefulness of Euclidean zoning, which has been blamed for blocking multifamily housing, exacerbating the housing crisis, perpetuating inequities in homeownership, and driving up carbon emissions. 

Roughly 33 states have passed laws to liberalize zoning and allow more density in single-family neighborhoods, and “Thousands of communities have re-legalized mixed-use development as well, seeking to blend housing with shops and restaurants in walking distance — the kind of neighborhood that Euclid made illegal.”

Zoning is a tool meant to make cities better. In the early 20th century, use-based zoning helped protect residential communities from the impacts of noxious uses. Today, the rules may need updating. “When it comes to land policy, a little fluidity is a virtue — an interplay between foundational principles and adjustments, given how times have changed.”

Thursday, February 19, 2026 in Bloomberg CityLab

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