A statute passed almost unanimously in 1973 turned out to be the most powerful environmental law in the country, and almost nobody who voted for it understood what they had done. This article explains how wildlife law actually works. It covers the listing decision that must ignore economics and the habitat designation that may not, the definition of take that reaches habitat modification and the case that upheld it, the consultation requirement that gives one agency a veto over every other, the permitting path that makes development possible, and the older statutes that impose strict liability without any of the modern process. It ends with what a landowner, a developer, and an advocate should each actually do.