This thesis explores the appeal of 'professionalism' to New Zealand journalists as an occupational ideal, as a collective strategy to advance their interests, and as a model of internal reform. As an explicit rejection of the 'traits based' analyses of journalistic professionalism drawn from the sociology of professions, this thesis applies an alternative approach which explores the changing nature of journalists' conceptions of professionalism over time, as well as the structures through which they have been conveyed. In doing so, this thesis offers insight into the historical development of the journalistic occupation, as well as its contemporary configuration. This thesis shows that during the post-war period, the representative organisation of New Zealand journalists, the New Zealand Journalists' Association (NZJA) appealed to the nature and importance of journalistic work to sustain journalists' claims to professionalism. NZJA leaders argued that the status of journalists did not reflect the importance of journalistic work to society relative to that of the 'accepted professions'. 'Professionalism' thus provided journalists a model for the reform of their occupation's organisation, educational, and self-regulatory structures during the twentieth century. However, the appeal of professionalism among New Zealand journalists has been tempered by the presence of conflicting occupational ideals and aspirations among members of the occupation, and the wider journalism industry. It is concluded that future reform initiatives will inevitably prove ineffectual unless the historical forces that have undermined contemporary New Zealand journalism's professional culture are acknowledged. A rethinking of the concept of 'journalistic professionalism' that focuses less on the presence or absence of certain professional traits, and more on their uses to promote journalists' professional consciousness and the quality of journalism, is a necessary starting point for future reform.