This chapter explores the nature and implications of judicial activity. It considers questions about the nature of judicial activity, and the attempts which have been made to create an understanding of the exercise of judicial discretion. The High Court’s decision in the Murray Islands case illustrates several issues to be considered in an analysis of judicial decision making. The controversy over the Murray Islands case of whether judges should ‘make’ or ‘declare’ law has resurrected an old jurisprudential chestnut which many thought to have been long buried by the recognition that the ‘reality of creative legal development’ does not sit easily within either paradigm. Liberal and formalist views of law rest on the assertion that there is a distinctively ‘legal’ body of reasoning completely distinguishable from other forms of reasoning. The jurisprudential debate about adjudication treats judicial activity as primarily the activity of higher appellate courts.