A well reported outcome of the current expansion in the use of computers within all areas of academic, commercial and industrial life, is the growing number of users without formal training in programming or computer technology. Such users wish simply to employ the machine as a tool in their daily work, and are not interested in becoffiing computer professionals or in understanding the details of their application system. People within this category come from a very wide range of educational and professional backgrounds, each individual ideally requiring a system carefully matched to the technical, psychological and social needs of his occupation. The chapters in this volume are concerned with the satisfaction of this ideal.