Political turmoil surrounding immigration at the federal level and the inability of Congress to pass comprehensive immigration reform have provided an opening for state and local governments to become more active in setting their own immigration-related policies. States largely dictate the resources, institutions, and opportunities immigrants can access: who can get a driver’s license or attend a state university, what languages are spoken in schools and public offices, how law enforcement interacts with the public, and even what schools teach students about history. In States of Belonging, an interdisciplinary team of immigration experts – Tomás R. Jiménez, Deborah J. Schildkraut, Yuen J. Huo, and John F. Dovidio – explore the interconnections among immigration policies, attitudes about immigrants and immigration, and sense of belonging in two neighboring states – Arizona and New Mexico – with divergent approaches to welcoming newcomers. Arizona and New Mexico are historically and demographically similar, but they differ in their immigration policies. Arizona has enacted unwelcoming policies towards immigrants, restricting the access of immigrants to state resources, social services, and public institutions. New Mexico is more welcoming, actively seeking to protect the rights of immigrants and extending access to state resources and institutions. The authors draw on an original survey and in-depth interviews of a cross-section of each state’s population to illustrate how these differing approaches affect the sense of belonging not only among immigrants, but among the U.S.-born as well. Respondents in Arizona, regardless of whether they were foreign- or native-born or their ethno-racial background, agreed that the state is unwelcoming to immigrants, and they pointed to Arizona’s restrictive policies as the primary factor. The sense of rejection perceived by Latinos in Arizona, including the foreign-born and the U.S.-born, was profound. They felt the effects of administrative and symbolic exclusions of the state’s unwelcoming policies as they went about their daily lives. New Mexico’s more welcoming approach had positive effects on the Latino immigrant population, and these policies contributed to an increased sense of belonging among U.S.-born Latinos and U.S.-born whites as well. The authors show that exposure to information about welcoming policies is associated with an improved sense of belonging across most population groups. They also find that the primary dividing line when it came to reactions to welcoming policies was political, not ethno-racial. Only self-identified Republicans, Latino as well as white, showed reduced feelings of belonging. States of Belonging demonstrates that welcoming policies cultivate a greater sense of belonging for immigrants and other state citizens, suggesting that policies aimed at helping immigrants gain a social, economic, and political foothold in this country can pay a broad societal dividend.