His teaching and research interests include minority political behavior, immigration policy, and demographic change. He is the author of Apart: Alienated and Engaged Muslims in the West (Oxford University Press 2010), The New Minority: White Working Class Politics in an Age of Immigration and Inequality (Oxford University Press 2016), and will soon publish Crossroads: Comparative Immigration Regimes in Times of Demographic Change (Cambridge University Press 2017). He is the editor of Silent Citizenship: The Politics of Marginality in Unequal Democracies (Routledge 2016), and has authored a dozen peer-reviewed articles. He has also provided commentaries for BBC, CNN, The Guardian, NPR, Politico, Reuters, and Vox. In 2007, Gest co-founded the Migration Studies Unit at the London School of Economics (LSE).