A noncompete is the only contract most workers sign that limits what they may do after the relationship ends, and it is enforced by a body of law that varies more between neighboring states than almost any other area of American practice. This article explains what a noncompete actually restrains, what courts examine when deciding whether to enforce one, and why the same document can be void in one state and fully enforceable across the river. It covers the related covenants — nonsolicitation, nondisclosure, and forfeiture provisions — that do much of the same work with different rules. It then covers the trade secret law that operates alongside them and that often provides the real remedy. It closes with the practical questions on both sides: what a departing employee should do first, and what an employer can realistically obtain.