Jos Twisk studied human movement sciences in Amsterdam and after his graduation he moved to epidemiology and from that into applied statistics. He specialised himself in the methodological field of longitudinal data analysis and multilevel/mixed model analysis and wrote three textbooks about it (all published by Cambridge University Press). Besides that, he wrote a textbook about applied biostatistics (in Dutch). He is also program director of the Epidemiology master programme in Amsterdam and he is head of the expertise centre of applied longitudinal data analysis. His main activities are teaching (courses in mixed model analysis, longitudinal data analysis, multilevel analysis and applied basic statistics), consulting, and applied methodological research. He (co-) authored more than 1000 peer reviewed international papers.