In this phase, the nature of the work done by the campaign shifts from capacity building to overtly challenging the status quo; it is a dramatic shift from preparation to action. From this point on there is no going back. Whatever your critical campaign action is (and it can take many forms) your action has to be an expression of the passion and commitment you have built up during the earlier phases of the campaign. To be successful, a challenge must be correctly targeted, fully resourced, perfectly timed, and the action must be swift and decisive. Therefore the objectives you set and the activities you carry out during the critical phase are very different from those of the Foundation and Build-up.

The critical phase should be designed to be short. Three factors are crucial to its success: first that the opposing factions are taken by surprise, second that their escape routes appear to have been closed or compromised, and third, that they are able to yield without losing face.

Many campaigns fail because they fail to take account of the nature of criticality, and get drawn into a protracted critical phase.