Numbers increasingly govern public services. Both policymaking activities and administrative control are increasingly structured around calculations such as cost-benefit analyses, estimates of social and financial returns, measurements of performance and risk, benchmarking, quantified impact assessments, ratings and rankings, all of which provide information in the form of a numerical representation. Through quantification, the public services have experienced a fundamental transformation from “government by rules” to “governance by numbers”, with fundamental implications not just for our understanding of the nature of public service itself, but also for wider debates about the nature of citizenship and democracy. This project scrutinizes the relationship between quantification, administrative capacity and democracy across three policy sectors (health/hospitals, higher education/universities, criminal justice/prisons) and four countries (France, Germany, Netherlands, UK). It offers a cross-national and cross-sectoral study of how managerialist ideas and instruments of quantification have been adopted and how they mattered. More specially, it examines (i) how quantification has travelled across sectors and states; (ii) relations between quantification and administrative capacity; and (iii) how quantification has redefined relations between public service and liberal democratic understandings of public welfare, notions of citizenship, equity, accountability and legitimacy.