Instances are common in law where more than one legal authority potentially governs a particular event, occurrence or transaction. When the outcome required by these authorities differs, which law governs? Beginning with the classic problem of choosing an applicable law in cases with facts touching more than one jurisdiction, this course explores the variety of theories and systems used to resolve this question. The course thus uses state/state conflicts to develop a set of approaches and then extends these to such other problems as adjudicatory jurisdiction, judgments, federal subject-matter jurisdiction, and public and private international law.