In markets we trust? Setting the boundaries of Market-Based Instruments in ecosystem services governance

A growing tendency to frame environmental problems as a failure to price ecosystemservices has coincidedwiththe rise of so-called "Market-Based Instruments" (MBIs). The aimof this introductory article to the special section "In markets we trust? Contrasting views on the performance and legitimacy of Market-Based Instruments in global environmental governance" is to promote critical reflection about the nature, scope and limits of MBIs in ecosystem services governance and to provide guidance on where the boundaries for the application of markets ought to be set. First,we examine the role thatmethodological assumptions and implicit normative positions play in shaping academic perception of the effectiveness and legitimacy of MBIs. Second,we examineMBIs in the broader ideological context and socio-political processes that have favored their development and implementation. Third, we test claims of the literature on MBIs against insights and data from case studies presented in the special section. Fourth, we discuss the scope and limits of markets in ecosystem services governance in the light of biophysical, institutional, and normative boundaries.We endwith a summary of concluding remarks fromthe special section and by identifying critical tasks for the scientific and policy agenda on ecosystem services governance.