This sixth volume of the Polish Yearbook of Law & Economics contains a collection of articles selected, following a separate review process, from papers delivered at 4th Polish Law & Economics Conference, which took place at the Warsaw School of Economics on October 23–24, 2015. About 70 scholars, students and practitioners were participants of this Conference organised by the Polish Association of Law & Economics (PSEAP) and Warsaw School of Economics, in cooperation with the Centre for Economic Analyses of Public Sector (CEAPS) at Faculty of Economic Sciences of the University of Warsaw.