Abstract The authors have recently developed a new approach to performing a Delphi study that does not involve the use of sequential “rounds” and as a result, greatly improves the efficiency of the process and shortens the time to perform such studies. This paper describes this process, RT Delphi, and illustrates its use in a decision-making application drawn from the Millennium Project of the American Council for the United Nations University. The illustrative application involves setting priorities among strategies for dealing with anticipated terrorist activities that might be initiated by a single deranged individual.