Book excerpt: One might mistakenly think that the long tradition of economic analysis in antitrust law would mean there is little new to say. Yet the field is surprisingly dynamic and changing. The specially commissioned chapters in this landmark volume offer a rigorous analysis of the field's most current and contentious issues. Focusing on those areas of antitrust economics that are most in flux, leading scholars discuss topics such as: mergers that create unilateral effects or eliminate potential competition; whether market definition is necessary; tying, bundled discounts, and loyalty discounts; a new theory of predatory pricing; assessing vertical price-fixing after Leegin; proving horizontal agreements after Twombly; modern analysis of monopsony power; the economics of antitrust enforcement; international antitrust issues; antitrust in regulated industries; the antitrust-patent intersection; and modern methods for measuring antitrust damages. Students and scholars of law and economics, law practitioners, regulators, and economists with an interest in industrial organization and consulting will find this seminal Handbook an essential and informative resource.