The author attempts to answer the following question: in an international legal system of which States are no longer the only subjects, what is the role that the consent of IOs plays in the creation of rights and obligations that apply on the international plane? The chapter reflects on the legal agency that IOs enjoy, qua subjects of international law, in the process of formation of general international law and in the acquisition of treaty rights and obligations. In so doing, it advances two claims. The first is that even though IO practice can and should be taken into account in the identification of customary rules, it is not a necessary element in the process of formation of those rules. The second claim of the chapter is that, under current law, IOs can only be bound by treaty rules to which they have consented, which may give rise to problematic gaps between the treaty obligations of IOs and the treaty obligations of their members. In pursuing those claims, the chapter offers some reflections on the systemic and normative implications of the formal involvement of IOs in the making of rules of general and conventional international law.

This chapter provides an in-depth analysis of the role reciprocity plays in treaties. First looking at treaty law and how reciprocity functions in the rules on reservations to treaties, the chapter goes on to examine reciprocity’s role in bilateral treaties, drawing on the examples of air transport agreements and energy agreements in particular, before looking at reciprocity’s role in multilateral treaties of the bilateralizable, interdependent, and integral types. It then analyzes treaties creating international organizations, particularly the EU and ILO, and differentiated obligations in environmental and trade law, illustrating how reciprocity operates in these types of instrument. Finally, the chapter addresses "objective regimes" and the effects of treaties on third parties. While some limitations exist on reciprocity, these do not depend on the substance of obligations but rather on the legal equality of the subjects involved.

This chapter addresess the operation of reciprocity in the enforcement of international law. It looks at the roles reciprocity may play in the consequences of a breach of international law, analyzing the exception of nonperformance and State responsibility. In particular, it analyzes the consequences that attach to the breach of erga omnes obligations or peremptory norms, and the rules and limitations on countermeasures. The structure and mechanisms of international responsibility demonstrate the persisting importance of reciprocity in international law and the structural limitations that international law’s horizontal nature poses to establishing specific consequences for breaches of community obligations.

The TPNW represents an unprecedented departure from current practice in that it is the first multilateral treaty to ban nuclear weapons. It is supported by 122 nations, representing a sizable contingent of the world’s population spanning various geographical divides. Although not celebrated by all nations, and vehemently opposed by nuclear-weapon states, its adoption at the UN General Assembly in July 2017 marks a fundamental departure from the status quo regarding armament matters. The primary purpose of this book was to examine the TPNW within the broader legal, diplomatic and political context in relation to the existing nuclear nonproliferation and disarmament framework in international law, exploring the influence of the Treaty from various perspectives and its potential impact on the nuclear architecture as it stands today.

While third states and international organisations often co-sign peace agreements in the capacity of witnesses or guarantors, little is understood of the legal consequences flowing from these roles. The chapter aims to fill this gap. First, it highlights that the mere designation of witness or guarantor leads to few consequences. Second, it analyses how specific third-party rights and obligations are established and conceptualised under VCLT rules, extended by analogy to intra-state peace agreements. Third, it provides a brief illustration of common third-party rights and obligations in peace agreements. Finally, it examines whether the involvement of third parties can internationalise an intra-state peace agreement, i.e. render it to be governed by international law. Bringing together views from the literature, jurisprudence and the preceding analysis on the structure of third-party rights and obligations, the chapter concludes that such rights and obligations can be internationalised, in a manner that can only extend to the agreement as a whole when inseparable from the rest of the agreement.

While third states and international organisations often co-sign peace agreements in the capacity of witnesses or guarantors, little is understood of the legal consequences flowing from these roles. The chapter aims to fill this gap. First, it highlights that the mere designation of witness or guarantor leads to few consequences. Second, it analyses how specific third-party rights and obligations are established and conceptualised under VCLT rules, extended by analogy to intra-state peace agreements. Third, it provides a brief illustration of common third-party rights and obligations in peace agreements. Finally, it examines whether the involvement of third parties can internationalise an intra-state peace agreement, i.e. render it to be governed by international law. Bringing together views from the literature, jurisprudence and the preceding analysis on the structure of third-party rights and obligations, the chapter concludes that such rights and obligations can be internationalised, in a manner that can only extend to the agreement as a whole when inseparable from the rest of the agreement.

In this chapter I discuss the responsibility of international organizations for human rights violations as a matter of substantive law. The central rules concerning the attribution of conduct to international organizations are analyzed, as are the relevant rules on indirect responsibility (complicity). Four potential sources of human rights obligations for international organizations are also identified: the constitutions and secondary law of the organizations themselves, treaty law, customary law, and general principles of law.

After the Torrey Canyon tanker disaster off the English coast in 1967, when the UK Government invoked necessity for the purpose of justifying protective conduct that infringed on the rights of another state, the community of states started deliberations on a special emergency treaty regime for maritime casualties that led to the Intervention Convention. This chapter analyses this framework as a prototypical special regime for emergency situations in order to deduct lessons for a possible cyber emergency treaty.

The chapter provides a general overview of the Handbook and identifies those who may be interested in and/or benefit from it. It explains that the aim of the Handbook is not only to describe treaty practice as it is, but also to suggest how to do it well. It explains what treaty practice is and sets out proposed criteria for good practice, with plenty of examples that meet these criteria. The chapter also introduces a useful analytical tool to enable each government and IO to identify and develop the best treaty practice for their circumstances, recognising that one size does not necessarily fit all.