This book covers the basics of the federal income taxation of partnerships and corporations including the taxation of LLCs, LLPs and S corporations. In addition, it alludes to a short list of other business enterprises. It is designed to be taught as two major components: partnerships and corporations. Both components use the traditional "cradle-to-grave" approach. Because of their practical importance, the book makes reference to Social Security taxes and estate taxes. There is no discussion of State income taxes. Although the book is comparatively short, the materials are dense and are heavily supplemented with problems. The cases have been extensively edited, and most footnotes in the original cases have been eliminated without any explicit reference to the fact of their elimination, other than the words in this paragraph. Case and statute citations of the court and commentators, as well as footnotes, have been omitted without so specifying; numbered footnotes are from the original materials but do not retain the original numbering, except by accident. The book is rich with problems that are scattered along the way, rather than at the end of each chapter. They are not especially difficult and are designed to build confidence while at the same time forcing students to review the central Code provisions and pertinent regulations.