Does the US administration exercise more informal influence over the World Bank when it has less control over US bilateral aid because of opposition from Congress? Replicating four studies of the World Bank, we show that years with a divided US government account for earlier findings of informal influence. This link between donor domestic politics and the exercise of influence in multilateral settings is important for understanding informality in international organizations and provides an alternate explanation to persistent questions about the role of international organizations in the international political economy.

Complex global and regional governance includes both the informality of governance institutions and informality around those institutions. National governments are only one category of actor, though an important one, among a more heterogeneous group of governors. The dynamics and evolution of globalization over time explain the emergence of complex governance in recent decades, an explanation that is complementary to those based on functionalism or domestic politics. Globalization alters actor incentive structures and reduces border effects, allowing nonstate and subnational actors to collaborate and reducing costs of participation in governance. Globalization has empowered actors: Emerging economies, INGOs, and MNCs. Globalization's future will continue to shape the prospects of complex governance.

Chapter 5 analyses the three challenges facing international tribunals considered in this book in investment treaty arbitration. Regarding the challenge of managing change, investment treaty arbitration displays similarities and differences with the inter-State tribunals studied. Using the example of the minimum standard of treatment, the chapter shows that like the inter-State tribunals studied, investment treaty tribunals contribute to broader processes of change in international legal norms. Yet differently from the other tribunals studied, investment treaty arbitration has an overriding focus on determining the permissible degree of change in host State regulation. In relation to scrutinising State conduct for compliance with international law, investment treaty arbitration raises comparable questions to the other international tribunals studied regarding the appropriate intensity of review and the methods of review used by adjudicators. Finally, the chapter considers why, unlike the inter-State tribunals studied, investment treaty tribunals rarely adjudicate in a facilitative, forward-looking manner that aims to complement post-adjudication cooperation between the parties.

Why do states choose informal organizations to govern global challenges? Using the global development regime as a piloting case, this article argues that different informal organizations serve different purposes. Informal intergovernmental organizations generate “club benefits” for member states, which arise from executive policy coordination behind closed doors. In contrast, transnational governance initiatives allow states to reap “risk-sharing benefits” in the production of global public goods by involving stakeholders. Using regression analysis for a set of development-related institutions, the analysis demonstrates that the two types of organizations are driven by different motivations. Complementary evidence is provided through case studies of two institutions: The IBSA Dialogue Forum (an informal intergovernmental organization) and the Global Partnership for Effective Development Cooperation (a transnational public-private partnership). The findings inform conceptual discussions of the informality of institutions while contributing to a better understanding of the design determinants of informal organizations.

Informal institutions in global governance are generally expected to favor powerful states. According to conventional arguments, procedural justice is best secured through formal institutional rules that constrain power, while informal institutions reinforce power asymmetries. This chapter revisits this position and asks, how and under what conditions can informal institutions enhance the voice and influence of less powerful or marginalized actors in global governance? The chapter argues that while informal institutions are useful to powerful states because they remove constraints to individual action, they can also be useful to less powerful states to the extent that they positively support action through social-integrative effects. Specifically, interactions within informal groups generate two types of social effects – capacity-building and coalition-building – that can enhance the voice of developing countries and increase their control over collective decisions. The chapter illustrates the arguments by profiling informal groups in the global governance of trade and finance.

We assess the development of informality in international climate policy on two levels: Whether informal organizations meaningfully contribute to climate change mitigation, and what role informality plays under the UN Framework Convention on Climate Change (UNFCCC). Proliferation of informal intergovernmental organizations (IIGOs) has enabled the move from a rigid list of countries with and without commitments, to the Paris Agreement, under which each country contributes to mitigation. Within the UNFCCC process, we find a “formality-informality cycle,” in which actors sometimes render rules and procedures more flexible and hence more efficient, only to suddenly reverse this trend at other times. Such a high-profile reversal occurred in Copenhagen in 2009. Subsequently, through the use of highly transparent negotiation procedures, trust in informality increased again, allowing negotiators to successfully override Nicaragua’s opposition in Paris in 2015. Similar formality-informality cycles can be observed on specific topics within the UNFCCC negotiations, such as international market mechanisms.

Chapter 4 analyses the three selected challenges facing international tribunals – managing change, reviewing State conduct for compliance with international law, and dispute resolution – in the International Court of Justice (ICJ)’s environmental case law. The ICJ has repeatedly adapted aging treaty frameworks given relevant developments in international law and has also faced the problem of change in relevant facts. While the terminology of a standard of review is not firmly established in the ICJ’s case law, the underlying functional problem – concerning the intensity of an international tribunal’s scrutiny of determinations made by domestic authorities – is clearly present. Although three-step proportionality analysis is not entrenched in the ICJ’s case law, the Court has repeatedly used a reasonableness-based test that operates similarly to least restrictive means testing. Finally, the ICJ often adjudicates in a forward-looking, facilitative manner, seeking to assist the parties to manage their relationship after adjudication. Throughout, the chapter reflects on how the ICJ’s practices are shaped by its institutional features, such as its lack of any compulsory jurisdiction.

Chapter 1 introduces the questions the book focuses on and explains its key contributions to literature on international adjudication. It introduces the three challenges facing international tribunals analysed throughout the book: managing change in applicable law or relevant facts, determining the appropriate standard and method of review when scrutinising State conduct for compliance with international law, and contributing to broader processes of dispute resolution. The chapter explains why the book focuses on environmental disputes, as such disputes lack a dedicated tribunal and are litigated across various regimes, and how it defines such disputes. It also justifies the choice of the four adjudication contexts focused upon (adjudication in the World Trade Organization, the UN Convention on the Law of the Sea, the International Court of Justice, and under investment treaties). The chapter also notes certain insights the book incorporates from methodological debates in comparative law, given its focus on identifying and explaining similarities and differences in how the three selected challenges are managed across the four adjudication contexts studied.