It is part of educational folklore that Australian State school systems are highly centralised. A corollary of that lore is that schools generally lack the organisational flexibility to provide adequately for the diverse educational needs of their students. This study tested these beliefs, especially as they related to state school systems in the states of Queensland and New South Wales. The researcher found that system-level directives are more prescriptive in the latter state. In both states, however, the proportion of time which must be devoted to prescribed activities, for both teachers and pupils, is less than many would expect. Even where head office directives appeared to be constraining, regional office staff can practice 'benign neglect' in their policing of the directives, if they can see that there are educationally sound reasons for doing so. A wide range of curricular structures was found within schools functioning in the same system. This indicated that a number of other elements, many less tangible, were influential in affecting a principal's ability to adjust curriculum structures. Of prime importance were a principal's perceptions of systemic reality, including system guidelines. The study found that there is sufficient substance in the folklore to give conservative principals an excuse to resist introducing innovations in their schools. Nevertheless, any principals who are determined to adapt their schools' operations to serve better the educational needs of their students are unlikely to be prevented by central directives.