Interaction design benefits from using the Delphi Method because it is a swift and systematic way to organize the scope and business focus of a project. 

Method

To determine this, I conduct one-to-one interviews with the people who care and know the most, initially asking them only to name what they think are the biggest issues.

After one round of initial interviews, I return to each and begin to determine what the range of issues are, and where differences might only be semantic. By the third round of interviews, the focus and goals are clearly in sight and language can be nailed down.

Results

The result is a continuum of variables underlying behavior and attitudes toward the project or issue. This investigation method produces a fine-tuned assessment of what users really experience/ feel/ need/ think about the subject.  

Timeframe

Consensus reached in the usual way (many long meetings that "go in circles") might otherwise take months.  Using Delphi, it can take 5 weeks total: 1 week to select/schedule interviews with "experts�, 3 weeks to conduct  all interviews, and 1 week to write report.

Preparation

Screening for and recruiting qualified participants will rely on clearly defined behaviors that are relevant to the larger project goals.

Additional Reading

An interactive but brief explanation of this methodology is found at:

http://www.ryerson.ca/~mjoppe/ResearchProcess/841TheDelphiMethod.htm