The aim of this thesis is to examine, in the form of a qualitative study, the formation of a criminal milieu in Sydney following the Great War. I shall consider the roles played by the prison system, and the police, judges, politicians and criminals themselves, in the making of this underworld subculture in an attempt to understand why the milieu developed as it did. The study investigates why and how the underworld evolved to the point where authorities felt its threat was serious enough to introduce draconian legislation to deal with it. My thesis will suggest that while state legislation had a crucial effect on the development of the milieu, criminals and their associates exercised a degree of individual and collective agency that also influenced the progress towards a culture of organised crime. I shall also look at some of the legal, social and political consequences of the consorting law to determine whether this legislation did, in fact, have the effect for which it was claimed to have been framed. The press played a critical, although indirect, part in the formation of a criminal milieu. While the various media appeared to act with autonomy, many of those, on both sides of the law, who engaged in conflict and the exercise of power and control in and around the underworld, sought to use them as a tool to achieve their various aims. The thesis explores the role of the tabloid and broadsheet newspapers and also their use by police and other authorities in the creation of a moral panic during the 1920s in relation to the prevalence of firearms, razor attacks, prostitution, drugs and gang battles. I shall then consider whether the passage of harsh legislation was justified by the actual level of criminal activity in Sydney, or whether it was simply a 'knee-jerk' reaction by politicians, fuelled by a moral panic initiated by police and the media.