The Dutch 'Toeslagenaffaire' made us all realise how important it is (in the legal relationship between citizens and the government) to always seek a balance in regulation and principles such as reasonableness, proportionality and service. Unfortunately, finding a just solution does not always prove easy for judges and government lawyers. For this reason, we developed a two-day masterclass in cooperation with ACLPA and professors, researchers and lecturers from the UvA and HvA.