Corporate sustainability has been defined in previous work (Sustainable Companies Project) as when market actors create value in ways which are, amongst other concerns, economically sustainable. In the context of this chapter, this means that corporate actions ought to satisfy the economic needs necessary for stable and resilient societies. There is a clear imperative that multinational companies do not respond to a notional concept of ‘shareholder primacy’ with an agenda dominated by the avoidance of tax liabilities. Nevertheless, in September 2016 the European Commission ruled that €13 billion in taxes was owed by a globally respected ‘corporate citizen’ – Apple Inc. – and that Ireland, a small member of the European Union, was responsible for collecting this tax. Ireland is appealing this decision. Avoidance (distinguished from illegal evasion) of tax on the scale we are considering is destructive and antithetical to sustainable actions. €13 billion represents a significant sum of monies required by governments to fund schools, hospitals, infrastructure and even aid programmes. This chapter places the interplay between Apple Inc., the Irish and US national tax authorities (California and US Federal), the European Commission and Organisation for Economic Co-operation and Development global tax initiatives such as Base Erosion Profit Shifting within the larger thematic scheme of this collection. In particular, the issues raised by the Apple tax story point to diverse forms of governance and the consequent complexity of the regulatory environment. In addition, this chapter considers a second theme: the roles of different actors, in this case the multinational corporation in all its forms, from large ‘headquarters’ based in California to a small but important set of ‘susbsidiaries’ based in Ireland. It addresses the interplay of national, international and supranational legislative systems, in addition to the concept of ‘regulatory ecology’, with particular focus on the relationship between legal and social norms (the acceptability of tax avoidance). The hypothesis is that this particular case study presents a ‘perfect storm’, allowing us to see how these regulatory arenas and types interface rather badly with each other. This is not a simple story of corrupt corporate or bureaucratic actions, but rather a presentation of a complex range of problems which cannot be addressed by rushing to ill-considered conclusions.