How do environmental norms and policies diffuse across borders? In this article, we argue that preferential trade agreements (PTAs) can play an important role in this process. Specifically, we argue that the US has long used PTAs as mechanisms to diffuse such norms, and show this through an empirical examination of three US PTAs, each from a distinct phase of US trade policy. We demonstrate how the US used the North American Free Trade Agreement, the Central American Free Trade Agreement, and the US-Peru Trade Promotion Agreement as vehicles to diffuse norms of (1) public participation in environmental policy-making, and (2) effective enforcement of environmental laws to trading partner nations. In doing so, we both illuminate a new mechanism of environmental norm diffusion and demonstrate the importance of this mechanism in changing environmental policy and practice across borders.

The entrée of climate change politics to the center stage of international relations has been accompanied by broad range of strategic linkages, which have produced various institutional interactions. This special issue takes stock of the wide range of ways that international regimes are strategically linked to climate change politics. We do this with a view to better understand both how climate change is shaping the global environmental political landscape, and is being shaped itself through strategic linkages to regimes both within (i.e. forests, biodiversity, fisheries, and desertification) and beyond (i.e. security and human rights) the environmental realm. The contributions that make up this special issue explore when, how, and by whom regime linkages should be pursued, how linkage politics are affecting regime development and function, and in turn how these changes are shaping the evolution of global environmental politics and problem solving writ large.

In this article I argue that, the Secretariat of the Convention on Biological Diversity (CBD), led by its autonomously entrepreneurial Executive Secretary, influences overlap management by strategically linking biodiversity and climate change issues. Specifically, the Secretariat marketed (filtered, framed, and reiterated) strategic frames of the biodiversity-climate change interface that reframed biodiversity from a passive victim of climate impacts, to an active player in climate response measures (i.e. adaptation). This reframing is significant in that a major hurdle to selling the benefits of biodiversity conservation to countries with more pressing development concerns has been the perceived limited relevance of conservation to human well-being. In emphasizing biodiversity's role in human adaptation and security, the Secretariat has begun to shape member state discourse surrounding the biodiversity-climate change linkage. Ultimately aimed at enriching our emerging theoretical understanding of the role of international bureaucracies in global governance, this article illuminates: (1) how the Secretariat understands and manages biodiversity-climate linkages; (2) the origins of the Secretariat's understanding and activities surrounding this issue; and (3) how Secretariat participation in overlap management is beginning to influence CBD political processes and outcomes.

This article builds on recent scholarship that explores the nature of secretariat influence in global governance. By combining data from interviews with WTO delegates and secretariat staff with document analysis, this study examines how the WTO secretariat is shaping trade-environment politics by using its bureaucratic authority to influence overlap management in the WTO. This study argues that secretariat influence is present, but varies in form across cases. It shows up in the forms noted by previous scholars in their examinations of UNEP secretariats (i.e. negotiation-facilitation, capacity building, and knowledge-brokering), but also in previously un-discussed forms of influence such as marketing convention norms, and litigation facilitation. It further argues that secretariat influence matters in that the WTO secretariat plays an important role in shaping the way trade-environment issues evolve within the WTO, shaping its own identity as a hybrid administrative-judicial organ, as well as in enhancing WTO legitimacy with the broader public.