Some of the most militant housing actions I have ever witnessed arose in opposition to buildings that don’t yet exist. I have seen occupations, disruptions, and even physical fights break out in order to halt state approvals for development projects. While it might seem a bit abstract to raise a ruckus in the present over construction in the future, everyone involved — from protesters to politicians to developers — understands the stakes.

The fight over housing is about both what is there and what isn’t: the cost of living in existing buildings, and the price of future developments. The pace and price of residential construction affects everything else in an area, from sewers and transit to taxes and schools. The rules guiding future development are therefore crucial to fights over both present and future housing conditions.

The way we make such decisions is known as planning. It is both the vision we have for our cities and towns, and the way we seek to implement it. There are many long-standing traditions of urban planning around the world, as practiced by both utopian socialists and cut-throat capitalists. Planning can be robust and seek comprehensive approaches to addressing the entire urban ecosystem, from physical development to environmental protection, or it can be narrow and carve out a limited role for government and a greater role for capital. Housing has long been a central concern for urban planners, from industrial revolution-era building safety codes to mid-century public housing projects.