Sarah's research and writing currently focuses on national and city responses to migrants with an irregular immigration status in Europe, including coordinating the JPI Urban Europe LoReMi project which is investigating responses in Vienna, Frankfurt and Cardiff. She was formerly Director of the Global Exchange on Migration and Diversity; and co-director of the City Initiative on Migrants with an Irregular Status in Europe, remaining on its Steering Committee. She was Chair of the Board of Directors of IMISCOE, the International Migration Research Network, from 2018 until Summer 2022.