Comparative research on gentrification is on the rise, especially since gentrification is no longer confined to historical, central neighbourhoods in First World countries, but also appeared in rural, new-built areas and Second World countries. In this paper we present our comparative approach to investigate gentrification processes in four European cities (Arnhem, Istanbul, Vienna, Zurich), which differs from previous studies in its use of assemblage theory as research framework. The multi-layered framework discerns three levels: metrics', interpretations', and practices'. We argue that many comparative studies mainly focus on metrics, while researching interpretations and practices instead - and how these three levels influence each other through processes of actualisation and counteractualisation - would enhance our knowledge on gentrification. In doing so, we aim to provide a precise account of the nested relations of different layers of empirical reality and thus respond to various calls in the debate to intensively examine geographies of gentrification'.