Delphi has come along way in its brief history and it has a long way to go. Since its invention about twenty years ago for the purpose of estimating the probable effects of a massive atomic bombing attack on the United states and its subsequent applications in the mid 60's to technological forecasting, it use has proliferated in the U.S. and abroad. While its principal area of application has remained that of technical forecasting, it has been used in many other contexts in which judgmental information is indispensable. These include normative forecasts; the ascertainment of values and preferences; estimates concerning the quality of life; simulated and real decision making; and what may be called 'inventive planning' by which is meant the identification (including invention) of potential measures that might be take to deal with a given problem situation and the assessment of such proposed measures with regard to their feasibility, desirability and effectiveness... The uses of Delphi to supply "soft" data in the social sciences and to provide decision makers with ready access to specialized expertise are of great potential importance, this volume will provide professional designers and users of Delphi survey with much needed background information.