The book examines contemporary immigration policy and immigrant assimilation with a focus on the adoption of sanctuary ordinances in US local governments in connection with Latino inmigration. It also investigates the adoption of antiimmigrant settlement local ordinances in many local governments with particular focus on local law enforcement positions taken on enforcement of federal immigration laws. The book investigates a wide range of countylevel characteristics of 3000 U.S. counties e.g. socioeconomic and demographic traits political culture social capital religious denominations present etc. to identify correlates of pro and antiimmigrant settlement. The book also features the analysis of a national survey and three targeted surveys in proimmigration San Francisco divided Maricopa and antiimmigration Tulsa counties to explore the individuallevel factors associated with sentiments on immigration policy. Finally the book presents findings from two case studies where active encouragement of Latino settlement Twin Falls ID and active opposition Hazleton PA characterize local reaction to Latino inmigration. The mixed methods study leads the authors to conclude that a funnel of causality concept path dependency prosocial attitudes and the concepts of moral panic and moral dialogue collectively lead to great insight into the question of why some communities are open and accepting while others are exclusionary.