The Delphi Technique is an essential project management technique that refers to an information gathering technique in which the opinions of those whose opinions are most valuable, traditionally industry experts, is solicited, with the ultimate hope and goal of attaining a consensus. Typically, the polling of these industry experts is done on an anonymous basis, in hopes of attaining opinions that are unfettered by fears or identifiability. The experts are presented with a series of questions in regards to the project, which is typically, but not always, presented to the expert by a third-party facilitator, in hopes of eliciting new ideas regarding specific project points. The responses from all experts are typically combined in the form of an overall summary, which is then provided to the experts for a review and for the opportunity to make further comments. This process typically results in consensus within a number of rounds, and this technique typically helps minimize bias, and minimizes the possibility that any one person can have too much influence on the outcomes.
This term is defined in the 3rd and the 4th edition of the PMBOK.