This chapter examines the legal legal of the Single Convention and its successor treaties. The passage of the Single Convention represented a high-water mark in the international regulatory system. While it contained little in terms of innovation, it streamlined the complex array of drug treaties, while moving the terrain of control forward marginally. It essentially solidified an economic regulatory framework for a global licit commodity market in certain essential medicines. To enforce this market it mandated certain action around controlling and prohibiting non-medical production and manufacturing. Key questions around dealing with ‘addiction’ and suppressing non-medical consumption were left largely unanswered. The US may have lost the battle around the Single Convention and control of the system in the 1960s but they would enter the 1970s ready to refight many of these battles, beginning with the declaration of the ‘war of drugs’ and an aggressive new round of bilateral drug diplomacy. Ultimately the ‘war on drugs’ was not an inevitable outgrowth of these documents, but instead represented a specific set of interpretations, bureaucratic and normative trajectories and member state implementations.

This chapter argues that whereas much of the past century was geared towards a legal and institutional homogenisation of international drug control, the coming decades appear underpinned by recourse to ‘policy pluralism’ as a mechanism to enable policy evolution. It is precisely these endogenous processes of pluralism, devolution and increasing diversity of global drug policies that provide the most promising avenues for various actors to influence policies at local, national, regional and international levels. It further argues that the international drug control system is undergoing a long-term process of fragmentation and evolution towards what international relations scholars in other spheres would term a ‘regime complex’. It concludes by suggesting that these endogenous regime changes likely provide the greatest opportunity to draw exogenous actors and regimes into the system’s orbit and thereby modernise and adapt drug policies to new global realities.