This forecasting method is based on the assumption that a complex problem can be better analyzed and solved by several experts than by a single one. The Delphi technique involves confronting ten to twenty experts with a problem, independently of each other, using standardized questionnaires, and obtaining their opinions. This questioning takes place over several rounds (usually three to four), which is why this procedure is very time-consuming. Each expert gives his or her assessment separately and anonymously until a modified, sufficiently homogeneous group opinion (Delphi judgment) emerges. In contrast to creativity-oriented brainstorming, the Delphi method focuses on the reduction of an individual opinion to a group assessment. (Source: Mehrmann/Wirtz, Gabler Management, GPM)