As a researcher, I consider myself to be primarily a policy sociologist. Policy is based on the basic assumption that humans can be influenced. Taking a closer look, we see that the theoretical assumptions that underlie policy instruments often prove to be incorrect or remain implicit or uncorroborated. Consequently, policy measures often have unintended consequences because users or target groups attach different meanings to policy instruments than policy makers or scholars had hoped for or assumed. I primarily assess the assumptions underlying specific policy measures, how these assumptions are connected to the motives and interests of the policy subjects, and what happens if the policy subjects do not act in accordance with the presuppositions underlying policy instruments. My research of the last few years focuses on the legitimization and implementation of health and safety policy, asylum policy, and crime and terrorism fighting.