Foreign policy – the anticipation of and response to disturbances flowing through a predetermined set of policy spaces – is by its nature a highly varied, unpredictable process. For this reason, we have departed from the usual way of depicting the foreign policy making process as a relatively fixed template of routines undertaken by regular participants resulting in identifiable outcomes. Rather, we characterised foreign policy as a set of activities that takes place across four distinct levels: the strategic, the contextual, the organisational and the operational. What remains to be done in setting the scene for discussing the institutions of policy-making and their policy environments is to characterise the policy process: how the different institutions and actors relate to each other; the “flow” of policy work through the components of the process; and the crucial institutional (as opposed to environmental) determinants of policy. We are particularly concerned with two questions that take centre stage in most discussions of policy-making: how are the various foreign policy institutions and actors involved in the policy process, and what is the extent of their influence?

To these questions, most models of foreign policy making have developed answers that cluster around a particular set of conventions about the foreign policy process. In this, they have been heavily influenced both by the US behaviouralist approach to assessing political power and influence, and by Graham Allison's highly influential study of foreign policy decision-making during the Cuban missile crisis, Essence of Decision.