This dissertation explores the intersection of two major developments in global environmental governance: the vision for a green economy and the growing influence of non-state actors. The work draws on multi-sited thick description to analyze how relationships between the state, market, and civil society are being reoriented towards global problems. Its focus is a non-binding agreement between California and Chiapas to create a market in carbon offsets credits for Reducing Emissions for Deforestation and forest Degradation (REDD). The study draws on three bodies of scholarship. From the institutionalist study of global environmental politics, it uses the ideas of orchestration, civil regulation, and private entrepreneurial authority to identity emerging alignments of state and non-state actors, premised on an exchange of public authority and private expertise. From concepts borrowed from science and technology studies, it inquires into the production, certification, and contestation of knowledge. From a constitutionalist perspective, it analyzes how new forms of public law and private expertise are reshaping foundational categories such as territory, authority, and rights. The analysis begins with general research questions applied to California and Chiapas, and the international space where groups influential in these sites are also active: 1) Where are new political and legal institutions emerging, and how are they structured? 2) What role does scientific, legal, and administrative expertise play in shaping these institutions, and vice versa? And 3) How are constitutional elements of the political order being reoriented towards these new spaces and away from the exclusive domain of the nation-state? The dissertation offers a number of propositions for combining institutionalist and constructivist approaches for the study of complex global governing arrangements. It argues that this can help identify constitutional reconfigurations that are not readily apparent using either approach alone.