The current xenophobic cultural environment in the United States makes it imperative that psychologists understand the nature of xenophobia and recognize its consequences. This article explores sociological, social psychological, and multicultural research to examine the causes of negative attitudes toward immigrants. Xenophobia is presented as a concept descriptive of a socially observable phenomenon. Historical and contemporary expressions of xenophobia in the United States are examined and compared with cross-cultural scholarship on negative attitudes toward immigrants. Last, suggestions are provided for how counseling psychologists can integrate an understanding of xenophobia into their clinical practice, training, research, and public policy advocacy. (Contains 1 table.)