In June 2012, President Obama instituted the Deferred Action for Childhood Arrivals program, which suspended deportations and authorized work permits for an estimated 1.76 million eligible young undocumented immigrants. As one of the most significant recent shifts in policy, this executive immigration action has been hotly contested. Conservatives decry it as presidential overreach, while immigrant advocates say it does too little to stop deportations. Broader congressional solutions have been elusive and the U.S. Supreme Court has blocked a 2014 policy that would have protected more undocumented immigrants, including the parents of U.S. citizens and legal permanent residents. As arguments over immigration reach new levels of toxicity in the 2016 elections, it is important to consider how the implementation of Deferred Action is faring. An array of stakeholders has worked hard to carry out this program, especially local governments, nonprofit service providers, unions, advocacy organizations, and foreign consulates. How have these stakeholders managed implementation and what lessons do their experiences hold for future immigration reform initiatives? We found answers by interviewing about 270 institutional informants in the San Francisco Bay Area, the Greater Houston Area, and the New York City Metro Area.