The Notitia Dignitatum is regarded as one of the most important sources for the administrative hierarchy, both civil and military, of the later Roman empire. However, due to numerous difficulties associated with the text, few large-scale studies have looked at this document as a whole. The aim of this thesis, therefore, is to provide a comprehensive examination of the Notitia Dignitatum as a historical source for the late Roman bureaucracy. I argue that the Notitia Dignitatum presents a misleadingly static picture of what was a dynamic imperial court system. In particular, I suggest that the inherent – and perhaps inevitable – limitations of this source arise from its narrow focus on the holders of the highest civilian and military offices and its often circumscribed account of their duties. I argue that we need to use additional evidence in order to gain a more rounded picture of the bureaucracy. Therefore, I look at such senior posts as the praetorian prefect or magister officiorum and their ability to accumulate responsibilities often far beyond those duties ascribed to them in the Notitia Dignitatum. More than this, I maintain that official office was not a reliable guide to actual influence. This is particularly evident in the power exercised by some eunuch cubicularii and the status accorded to certain groups left out of the Notitia Dignitatum, not least imperial women and Christian bishops. In this way, I make evident the limitations of the Notitia Dignitatum as a historical source when it is studied in isolation. At the very least, the Notitia provides us with incomplete and so misleading information and, as a result, its usefulness as an accurate guide to the bureaucratic system must be questioned. In addition, it also leaves open the possibility of a more systematic misrepresentation of the administrative structure of the late Roman empire. By approaching the Notitia Dignitatum in a comprehensive way, I suggest that we can get a greater insight into its particular perspective and, as a result, its particular purpose and context.