One question that has been unresolved since the current phase of extremism began in the early- to mid-1990s has been whether or not there is a global structure to the jihadi phenomenon. This paper argues that no such definable structure exists, although regional, national, and local networks may well share common objectives and ideological ambitions. There has, in short, been a process of global branding that has developed that, in structural terms, corresponds to a ‘network of networks’. These objectives and the related praxis, moreover, have evolved over the years, going through three distinct stages of development, encapsulated in the strategic distinctions between al-Qa’ida, Ansar al-Shar’ia, and the Islamic State (Da’ish). Allied to this is a second consideration, namely that the formal ideological inspiration and justification for extremist activities is a set of integrated common insights that form a coherent ideology derived from a literalist interpretation of Islam, Salafism. A further aspect of the Salafi–jihadi phenomenon is to what degree this formal ideology is the real explanation of the appeal of these movements to their adherents, particularly to the so-called ‘foreign fighters’ – those who volunteer from countries not directly implicated in the specific conflicts in which they participate. This paper will argue that the phenomenon is far more complex than the superficial appeal of jihadist ideology would suggest. Finally, the paper will attempt to sketch out what the underlying causes of the intense wave of extremism sweeping the Middle East and North Africa might be and to what extent ‘blow-back’ from returning jihadis should be of concern to home governments.