This Festschrift honours Hartmut Kliemt on the occasion of his sixtieth birthday. Hartmut Kliemt’s work covers a huge number of topics, including publications on John Rawls’ theory of justice, Robert Nozick’s libertarianism or James Buchanan’s constitutionalism, the problems of cloning, legal punishment, state power, anarchism, the model of homo oeconomicus, game theory, the philosophy of science, ethics, the welfare state, the theory of law, rationing in health care, organ transplantation and homeopathy …