Reports the results of a qualitative, cross-sectional study involving a survey of 549 teachers′ perceptions of the Unit Curriculum system in 22 metropolitan state senior high schools in Perth, Western Australia, in the context of system-wide change, within a centralized educational system. Surveyed perceptions of six general variables applied to the specific case of the Unit Curriculum system. These variables are: perceived cost benefit to the teacher; perceived practicality in the classroom; alleviation of fears and concerns; participation in school decisions on aspects affecting the classrooms; perceived support from senior staff; and feelings towards the previous system compared to the new system. Suggests these variables offer pointers to educational administrators on how best to tailor system-wide changes so that teachers will be more receptive to the changes in the implementation stage.