This fourth volume of the Polish Yearbook of Law & Economics contains a collection of articles selected, following a separate review process, from papers delivered at the 30th Annual Meeting of the European Association of Law and Economics (EALE), which took place at the University of Warsaw on September 26-28, 2013. More than 200 scholars from 25 countries were participants of this Conference organised by the Polish Association of Law & Economics (PSEAP) in cooperation with the Centre for Economic Analyses of Public Sector (CEAPS) at Faculty of Economic Sciences of the University of Warsaw, as well as Warsaw School of Economics.