In this chapter I want to show how some of the understandings of complexity science can help us to understand the processes occurring in school. We will look at events in three schools, drawn from my own research, over a period of time from the arrival of a new head. I believe that this longer-term view enables us to see some of the complexity concepts in action. For example, they show that outcomes are generally co-determined by the effects of several mechanisms, and the way new forms emerge through self-organisation at the edge of chaos. The main description will concentrate on Beldene Secondary School, with shorter supportive descriptions from the other two, Enderby and Thornwood. This is for brevity, since similar overall processes can be seen in each, and may be summarised as shown in Figure 4.1.