For more than two decades, he has been a researcher, practitioner and policy advisor on issues relating to refugees, forced migration and peacebuilding. In recent years, he has undertaken field research in Burundi, Guinea, Kenya, India, Tanzania and Thailand, and has presented his research in New York, Geneva, London, Ottawa, Bangkok, Nairobi, Dar es Salaam and elsewhere. He has worked as a Consultant for the United Nations High Commissioner for Refugees (UNHCR) in India, Cameroon, Guinea and its Geneva Headquarters. He is author of Refugees, the State and the Politics of Asylum in Africa (Palgrave Macmillan, 2009), co-author (with Alexander Betts and Gil Loescher) of UNHCR: The Politics and Practice of Refugee Protection (Routledge, 2012), and co-editor of Protracted Refugee Situations: Political, Human Rights and Security Implications (UN University Press, 2008).