Claire Adida is Assistant Professor of Political Science at the University of California, San Diego, where she is also a faculty affiliate with the Center for Comparative Immigration Studies and with the Policy Design and Evaluation Lab. Her work has been published in the Proceedings of the National Academy of Sciences, Comparative Political Studies and Economics and Politics. Her research applies experimental, survey and interview methods to the study of ethnic politics. Adida's fieldwork has taken her to Nigeria, Niger, Benin, Ghana, Uganda and South Africa.

• 1. Introduction; 2. Immigrants and their leaders; 3. Immigrant exclusion from host societies; 4. Alternative explanations; 5. Mass immigrant expulsions in Africa; 6. Conclusion; Appendices.

Claire Adida is Assistant Professor of Political Science at the University of California, San Diego, where she is also a faculty affiliate with the Center for Comparative Immigration Studies and with the Policy Design and Evaluation Lab. Her work has been published in the Proceedings of the National Academy of Sciences, Comparative Political Studies and Economics and Politics. Her research applies experimental, survey and interview methods to the study of ethnic politics. Adida's fieldwork has taken her to Nigeria, Niger, Benin, Ghana, Uganda and South Africa.

• 1. Introduction; 2. Immigrants and their leaders; 3. Immigrant exclusion from host societies; 4. Alternative explanations; 5. Mass immigrant expulsions in Africa; 6. Conclusion; Appendices.

Claire Adida is Assistant Professor of Political Science at the University of California, San Diego, where she is also a faculty affiliate with the Center for Comparative Immigration Studies and with the Policy Design and Evaluation Lab. Her work has been published in the Proceedings of the National Academy of Sciences, Comparative Political Studies and Economics and Politics. Her research applies experimental, survey and interview methods to the study of ethnic politics. Adida's fieldwork has taken her to Nigeria, Niger, Benin, Ghana, Uganda and South Africa.

• 1. Introduction; 2. Immigrants and their leaders; 3. Immigrant exclusion from host societies; 4. Alternative explanations; 5. Mass immigrant expulsions in Africa; 6. Conclusion; Appendices.