Authoritative. Analytical. Contemporary. Thoroughly updated based on recent scholarship and current events, American Government: Power and Purpose remains the gold standard for teaching a political scientific perspective on American government. Thorough analysis of the 2018 midterm elections and the first years of the Trump presidency make this revision more current and authoritative than ever.American Government: Power and Purpose (Core Fifteenth Edition) 15th Edition by Stephen Ansolabehere; Benjamin Ginsberg; Theodore J. Lowi; Kenneth A. Shepsle and Publisher W. W. Norton & Company. ISBNs: 9780393675047, 0393675041. The print version of this textbook is ISBN: 9780393675009, 0393675009.