Three separate legal regimes decide what may leave the United States, what technology a foreign national may see, and whom an American company may deal with at all: the Export Administration Regulations for dual-use items, the International Traffic in Arms Regulations for defense articles, and the sanctions programs administered by the Office of Foreign Assets Control. This guide maps all three from the ground up: how to determine jurisdiction, how to read an ECCN against the Country Chart, when a license exception or EAR99 saves you, how the de minimis and foreign direct product rules project U.S. law onto foreign-made goods, and how end-use and end-user controls like the Entity List override everything else. It explains the deemed export rule that turns an ordinary hiring decision into an export transaction, the ITAR's see-through logic and registration and agreement architecture, and the OFAC framework of blocking, rejection, the 50 Percent Rule, facilitation, and secondary sanctions. It then turns to compliance in practice: screening, red flags, recordkeeping, the antiboycott rules, voluntary self-disclosure and what it is actually worth, and the civil, criminal, and administrative penalties that make this the highest-stakes compliance area most companies never think about. A running hypothetical about a semiconductor manufacturer named Northgate Silicon carries the doctrine from classification through crisis.