He studied both public administration (MA) and organization studies (MSc) at Tilburg University. Here, he also obtained his Ph. D in psychometrics. He is involved in several big data projects, e.g. on sustainable procurement for the Belgium federal government and on personality characteristics in governmental job ads. Kruyen is co-editing a book on comparative research methods in public administration, responsible for the methodological chapters. He supervises Ph. D students and teaches statistics, comparative research methods, and organizational psychology.