Immigration policy once played only a small role in policy debates—but the 2016 election changed that. Immigration has since become one of the most hotly debated policies in the country and remains a major focus of the White House’s agenda. Key to these debates are questions over how immigrants actually affect the U.S. economy. Do immigrants depress wages for low-income Americans? Do they have negative effects on American economic and cultural institutions? The Fall 2017 edition of the Cato Journal is dedicated to unpacking these questions, presenting the research of leading scholars in this field. It draws from presentations at Cato’s September 2016 conference, “Immigration Economics.” The resulting articles discuss how immigration affects housing prices; what impact immigration has on neighborhood segregation; and how immigrants promote entrepreneurship, as well as several articles discussing America’s approach to border security. Contributors include Giovanni Peri of the University of California, Davis; Ethan Lewis of Dartmouth College; Douglas S. Massey of Princeton University; Susan M. Wachter of the University of Pennsylvania; and Benjamin Powell of the Texas Tech Institute. In the introduction, Cato immigration policy analyst Alex Nowrasteh, who coedited this edition with Cato Journal editor Jim Dorn, notes that immigration tends to be an emotional issue for most Americans. “Our hope is that this issue of Cato Journal will help cool some of those emotions and instead shed light on this important policy debate,” he writes.