Changes in approach are not usually immediate, wholehearted or effective. Indeed, anomalies are rarely so overwhelming and blindingly obvious that scholars are willing to jettison their intellectual baggage in order to re-equip themselves with a new set, which happens to be conveniently waiting, complete and convincing, ready for an instant switch. Normally it takes time and is the outcome of a messy and confused process. Although realism achieved an acknowledged salience, in the 1950s ‘anomalies’ began to disturb that remarkable state of intellectual cohesion. Some were red herrings in so far as the intellectual development of the field was concerned, such as behaviouralism, since it became evident eventually, but not until after a fierce intellectual debate characterised by many intemperate ad hominem exchanges, that behaviouralism was more a question of methodological proclivities than one of conceptual differences. ‘Color It Morgenthau’ was the title of a highly influential conference paper, 1 which demonstrated, in an authoritative manner, that most ‘behavioural’ research was firmly embedded in the realist framework. Other developments were not red herrings, but, although identifying anomalies in realism, they did not propose dispensing with it as a framework, in part because they were only concerned with aspects of the framework and in part because there was no convincing alternative readily available. Progressively, however, other approaches such as world society and structuralism were sketched out and their ancient intellectual provenances explored.