This is the fifth version of this textbook, updated through December 2017 for use beginning January 2018, incorporating the Tax Cuts and Jobs Act. This textbook is not intended to be an exhaustive treatise; rather, it is intended to be far more useful than that for beginning tax law students by equipping the novice not merely with unmoored detail but rather with a rich blueprint that illuminates the deeper structural framework on which that detail hangs (sometimes crookedly). Chapter 1 outlines the conceptual meaning of the term “income” for uniquely tax purposes (as opposed to financial accounting or trust law purposes, for example) and examines the Internal Revenue Code provisions that translate this larger conceptual construct into posit...