Chapter 1 sets the historical and theoretical background of the book. It starts by describing the regulatory battles that took place from the 1970s to adopt more stringent tobacco control measures. Then, it illustrates how the negotiations of the WHO Framework Convention on Tobacco Control and the subsequent WTO and international investment disputes can be considered the internationalisation of the tobacco wars. In this context, the concept of ‘lawfare’ is introduced as a descriptive device and analytical tool for the analysis of the book. The second part of the introduction introduces the second fil rouge of the book: evidence. It begins by defining the notion of evidence and by showing how, in the context of tobacco control, it can refer to different bodies of evidence that pertain both to the risk assessment and risk management dimension of tobacco control measures. This second part, moreover, shows how evidence has always been one of the key points of contention in the tobacco wars and has continued to be so in the international tobacco control lawfare. The introduction concludes with an explanation of the methodology employed, a reflection on its limits, and an outline of the content of the book.