The term "sanctuary city" gained a new level of national recognition during the 2016 United States presidential election, and immigration policies and debates have remained a top issue since Donald Trump was elected President. The battle over immigration and deportation will be waged on many fronts in the coming years, but sanctuary cities — municipalities that resist the national government's efforts to enforce immigration laws — are likely to be on the front lines for the immediate future, and social workers and others in the helping professions have vital roles to play. In this book, Melvin Delgado offers a compelling case for the centrality of sanctuary cities' cause to the very mission and professional identity of social workers and others in the human services and mental health professions. The text also presents a historical perspective on the rise of the sanctuary movements of the 1970s and 2000s, giving context for the current environment and immigration debate. It serves as a helpful resource for human service practitioners, academics, and the general public alike.