Chapter 10. Experimental Evaluations of Policy Instruments Experimental methods have recently been used to evaluate environmental policy instruments in particular – and most suitably it seems – emissions trading programs of various designs. Some studies have focused on domestic emissions trading programs while others have focused on international programs in particular ones related to greenhouse gases. Much emphasis has been put on investigating the implications of market power in emissions trading. Other topics of the experimental studies reviewed here include the relative merits of different policy instruments (permits taxes standards) and the possibility of eliminating the need for conventional environmental policy through application of the Coase theorem.