A controlled, individual in-depth interview, including a feedback session.

We use this method in:

How does the method work?

With the Delphi method, experts from relevant disciplines are first identified through a Trendcycle and then recruited to participate in a multi-step inquiry. During the first wave of questioning, participants are interviewed in depth enabling the researchers to highlight and weight the relevant aspects ensuring a 360° perspective on the research topic. During the analysis, a range of opinions about different aspects would be identified. This range of perspective is then addressed in a second wave in form of a questionnaire by the original group of experts, in specific cases even with additional experts, where the results of the first wave are presented to the group in anonymity. This allows individuals to reassess their own position, especially while holding opinions at the extremes of the range as well as provide reasoning, feedback and further details of their own positions. If this process eludes satisfactory streamlining of positions, further waves could be conducted.

In a sense, the Delphi method is a controlled individual in-depth group interview with a feedback loop. In most cases, groups of experts move through this method toward consensus; but even when this does not occur, the reasoning for disparate positions becomes crystal clear. Researchers can make informed predictions based on these reasons as well as on the context of the study.


Because it is a qualitative tool, the Delphi method does not (and is not intended to) produce statistically significant results. The results represent the synthesis of opinions of the key experts in a field or area of research, no more, no less.

Common questions draw from the following categories:

  • 1.

    Forecasts of future developments: when or in what timeframe is an event or development expected to occur?

  • 2.

    Desirability of future state: should an event or development occur, or does it pose a threat or inconvenience to society or a specific group of people, what are recommendations?

  • 3.

    Questions of implementation: who, what, when, where, and how much and to what end.