ABSTRACT
Although most people like to believe that they make rational and logical decisions and expect that national policy-makers would do the same, Simon1 and many writers since have demonstrated that rationality is limited by human fallibility and/or by environmental constraints. One of the functions of groups is to overcome such limitations but the existence of a group is no guarantee that decision outcomes will be good. Decision-making pathologies do exist and one of these, that can occur when vital decisions are to be made, is groupthink. The flawed decisions that result from groupthink can lead to potentially disastrous outcomes: hence it is important that the phenomenon is well-understood by those charged with making vital decisions within the arenas of defence, security and peacekeeping.
