Zoning decides what a person may build, where, how tall, how close to the line, and for what purpose. This article explains where that authority comes from, why it survives constitutional challenge, and how the ordinary machinery of districts, permits, variances, and appeals actually operates. It walks through the difference between a use that is permitted, one that requires discretionary approval, and one that is simply forbidden, and it explains what happens to a use that was lawful before the rules changed. It covers the federal statutes that override local zoning in specific settings, including fair housing, disability accommodation, religious land use, and wireless facilities. It also explains why the hearing, not the lawsuit, is where most land use disputes are actually won. Examples run throughout, drawn from the situations that recur: the addition that violates a setback, the home business that outgrows its district, and the neighbor who objects. The article is written for property owners, small developers, and the lawyers who advise them.