Book excerpt: Figuring Out the Tax recounts the forgotten early development of the federal income tax in the US, resulting from the interplay between Congress and the Treasury Department in the decades following the enactment of the tax in 1913. It covers a wide range of topics including the income tax treatments of marriage, capital losses, charitable contributions and homeownership, as well as the rise, demise and resurrection of income tax withholding. Lawrence Zelenak deftly illustrates how the income tax achieved its current form through a range of stories which are new to tax history scholarship and involve some remarkable personalities and surprising plot twists. Although of particular interest to tax academics and professionals, this book will also serve as a useful introduction to the development of income tax for undergraduate students and law students.