Dr Alvaro Martinez-Perez is lecturer in International and Comparative Social Research Methods at the Department of Sociological Studies (University of Sheffield). Prior to joining the University of Sheffield he worked as an evaluator of public policies for the Government of the Autonomous Province of Trento (IRVAPP - Fondazione Bruno Kessler, Italy) and as a postdoctoral researcher at the Department of Sociology and Organisational Analysis at the University of Barcelona. His research interests include social stratification and inequalities in the family, gender, labour market and education; he is also interested in electoral behaviour and in business and management key areas such as undeclared economy and informal work. He is an expert in quantitative social research methods.