“Traditionally, statutory regulation was viewed as the primary mechanism for achieving environmental and social change. Its uniform system and top down implementation was expected to engineer social and environmental change at every location. However, this vision never constituted an entirely satisfactory empirical account of the realities of environmental governance, and there is significant variance in how communities and governments seek to resolve environmental challenges. The last four decades have seen an expansion in environmental governance by non-state actors, often in response to the perceived inefficiencies and limits of traditional legal regulation (that is, hierarchical government control, detailed and rigid state rules and judicial enforcement).” This chapter from Implementing Environmental Law argues that “while legal regulation has had some success in curbing point source pollution, it has fallen far short in addressing complex challenges such as biodiversity, water extraction and diffuse pollution from agriculture. To tackle these ‘wicked problems,’ business, civil society and governments have developed a range of tools such as market instruments, voluntarism, self-regulation and (importantly for this chapter), collaboration.”