This thesis is a study of the development of the London Society of Compositors from the formation of the Society in 1848 until the separation of news compositors from book compositors, for all negotiations concerning news compositors' wage rates and working conditions, following the Hampton Dispute of 1906. This study examines both the growth of the London Society of Compositors and the trends of change and continuity among metropolitan compositors during the second half of the nineteenth century, and it addresses itself to issues in trade union history, to contemporary concepts in the social history of Victorian society and also to aspects of the political press. Within the context of the metropolitan composing trade this study seeks firstly, to explain the presence in Victorian London of a trade union whose organization is archaic and whose level of craft control vis-a-vis employers is singular; secondly, it attempts to explain and to examine the persistence and the pervasive influence of compositors' craft ideology whose form and functions are fifteenth century in origin; thirdly, it considers the impact of the growth of the metropolitan printing industry upon the LSC; fourthly, it examines the union's response to political developments in British society in the second half of the nineteenth century; finally, this thesis throws light on the involvement of some metropolitan compositors in the radical and socialist press in Victorian London.