The project MATISSE was a Marie Skłodowska-Curie Action funded by the Horizon 2020 and it was hosted by the School of Geography, University of Leeds from May 2019 until August 2021 (grant agreement 79561). Inspired from dialogues in Critical Urban Studies, Urban Political Economy and Social and Spatial Justice, this project looked into the process of housing financialisation in Greece and in Spain, by exploring comparatively the cities of Athens and Barcelona. It investigated austerity policies, the investment strategies of transnational investors in Spain and Greece and the consequences this has for households facing housing unaffordability pressures. More precisely, MATISSE’s research objectives were to: (i) understand how policies of debt and restructuring are redefining property markets at the local level; (ii) trace investment strategies of transnational investors and their practices as credit and home-owners; and, (iii) ascertain the social and spatial implications for people when homes as mortgages, or austerity-induced debt, are auctioned or bought by transnational investors. It involved an interdisciplinary research action with policy implications for the governance of inclusive, innovative, and reflective societies, fully responding to the challenges set out in the Horizon 2020 ‘Societal challenges’ programme.