Whether you are a sole proprietor of a pharmacy operation, a member of a partnership or a limited liability company that operates a pharmacy, a shareholder of an incorporated pharmacy operation, or an employee of any of the foregoing, you will be subject to a variety of taxes as the result of your activities. This chapter begins with the general theories of taxation, including the constitutional underpinnings of taxation and the limitations on the taxing power. It then provides a general overview of the basic framework of federal income taxation and describes the federal income taxation applicable to individuals, partnerships, and corporations. The remaining sections discuss other federal taxes, including Social Security taxes, the Medicare tax, and excise taxes. Finally, the chapter concludes with a discussion of state and local taxation.