Javier Rujas is Assistant Professor at the Department of Sociology: Methodology and Theory, Complutense University of Madrid (UCM). He holds a PhD in Sociology (UCM, 2015), with a thesis on “school failure” in Spain. Between 2017 and 2021, he taught sociology at the University of Burgos. He has been visiting scholar at the Centre Européen de Sociologie et Science Politique (CESSP, EHESS Paris), and the Institute of Education (IOE, London). He is also founding member of the social research cooperative Indaga (www.indaga.org), where he worked between 2015 and 2018. His research interests include sociology of education, social and educational inequalities, school failure, school leaving and return, the public construction of educational problems, education policy enactments and institutional devices, educational trajectories and transitions to upper secondary education.