Within the nuclear field, a vast body of knowledge, involving scientific, technical and managerial fields, is distributed among many organizations of different types. Managing and provisioning distributed knowledge is therefore becoming one of the major challenges in federated organizational environments. This publication provides information to organizations dealing with nuclear knowledge and its management. It covers an introduction to semantic information technologies, the Worldwide Web standards developed for interoperability, the construction of knowledge bases on the basis of distributed knowledge, and the development of knowledge driven applications. In addition to providing insight into the development of distributed knowledge bases, the intent of this publication is to provide examples of applications of semantic technologies specifically in the nuclear field.