The research programme “Regulatory Instruments in the Real World” investigates the steering effect of different legal instruments (“regulatory instruments”). Regulatory instruments are all legal norms with which the legislator attempts to steer the behaviour of addressees in the public interest, such as prohibitions, commands, fines, incentive taxes, occupational bans, and many more. 
The same regulatory goal can be pursued with a variety of different regulatory instruments. The aim of the research programme is to empirically compare the regulatory instruments on the basis of the categories “effectiveness”, “side effects” and “costs”. The results of this research not only expand our basic knowledge of how the law works, but also have important implications for the practice of law-making, the authorities and the courts.