The law-and-economics movement remains a dominant force in American private law, even though courts and commentators recognize that many of its assumptions are implausible and that efficiency is not the law's only goal. This book adds to the debate by showing that many leading law-and-economics arguments fail on their own terms, even for those who accept their most important assumptions and goals. Adopting an analytical approach and using some law-and-economics methods against the leading arguments in that field, Shawn Bayern shows that economic thinking fails to explain or justify most rules in the common law. Bayern masterfully surveys leading law-and-economics arguments in tort, contract, and property law and shows them to be fragile, self-contradictory, or otherwise problematic. Those who accept that efficiency is important should not be persuaded by the kind of law-and-economics arguments that have remained in vogue among legal scholars for decades.