This chapter develops a conceptual, methodological and political framework for cultivating new forms of sustainable blue economy. The blue economy is a discursive project that seeks to assemble diverse economic activities taking place in coastal and ocean seascapes. The chapter examines how 'blue economy' thinking in New Zealand is being used as a platform to address these interests and concerns. It argues that such thinking directs attention in three novel directions: a re-categorisation of economy; new economic objects of concern; and to a potential politics of economic rent and social return. Actualised blue economies might be interpreted as entrepreneurial, investment and management initiatives that draw on marine environments to create economic and social values that sustain or enhance the resourcefulness of those environments and their communities. One approach is to re-categorise actualised economies to build a new grid of intelligibility with which to think, act and generate understandings useful to decision-makers.