Most local zoning ordinances follow the same basic formula, separately designating residential areas, commercial areas, and industrial areas, and keeping them apart.

This formula is based on an early 20th- century model from the last time the federal government provided significant zoning guidance: the Standard Zoning Enabling Act of 1925. By separating these different types of development, traditional zoning codes increase the distance between daily needs.

Combined with the transportation policies that prioritize vehicle movement above all else, zoning standards result in more driving and effectively ensure that new development will prioritize the movement of vehicles.

Today, government-mandated zoning requirements prevent the market from adding to the supply of walkable, transit-served communities to meet growing demand, driving up property values in these areas dramatically, making them unaffordable to those who could benefit the most. Despite the market and consumer demand for more housing (and housing types) in built-up areas and in walkable, connected neighborhoods, it is illegal to build anything except single-family detached houses on roughly 75 percent of land in most cities.

These laws have profound negative impacts. Artificially limiting the supply of housing in walkable, transit-served areas directly leads to a lack of access to and displacement of lower-income residents, exacerbates inequality in the process, and redirects growth into sprawling areas.

As with the zoning codes noted above, these results force people to drive further for everything, cut off people without a car from necessities too far away or too dangerous to walk to, generate traffic congestion, and create the counterproductive call to expand roads to accommodate the additional traffic.