The purpose of science education has long been debated. Attempts to define scientific literacy provided a focus for the debate and have been driven by the widely held view that science education should stimulate behavioural changes to ensure a sustainable future. It has also led researchers to try and determine what makes science purposeful for students, and what scientific knowledge and skills adults need. The curricular reforms proposed as a result of these processes attempt to challenge practitioners' established views of secondary science education. It is expected that the reforms will only produce the desired effects, if practitioners are provided with different levels of support and professional freedom sufficient to enable them take ownership of the change in paradigm. Initial teacher training, undergraduate science programmes and even the design of science classrooms, all have a part of play in bringing about successful reform.