The primary aim of the handbook series will be to include as much useful data as possible for the specialist needing ready access for the solution of problems most likely to arise in the radiation protection professions. However, some selected review of fundamental concepts is also included to enable persons with a basic science or engineering background to acquire the necessary knowledge to solve a majority of problems in especially important aspects of radiation protection. Also since the profession is broad in discipline, an attempt has been made to fulfil the frequent need of professionals for a refresher course in some of the more important fundamentals needed to utilize data included in the handbook. Principles of management, organization, and procedures related to radiation safety will also be summarized in later volumes, with attention to presentation of methods for establishing new radiation safety programs based on the accumulated experience of others.