From USIP: Scenarios for the Insurgency in Iraq
...Participants in the three scenario workshops, held in November 2005, January 2006, and April 2006, sought to anticipate possible outcomes of the insurgency in Iraq. To do this they tried to understand the underlying forces and trends and the uncertainties related to their development and impacts. Unlike most academic and intelligence analyses—which focus mostly on information known with confidence—scenario analysis focuses on uncertainties. This term refers to factors or forces whose development or impacts are impossible to forecast accurately.

Participants made no assumptions regarding historical continuity or change. Instead they focused on plausible developments in underlying forces and trends—in this case over a three- to seven-year period.

They considered multiple potential outcomes and the developments that produce them rather than forecasting a single outcome. Given the complexity of the insurgency, we recognized the value of having several potential outcomes for which we would evaluate U.S. and Iraqi goals and options.

The scenario process exposes and illuminates not simply the views of expert observers, but the assumptions underlying those views and the implications of conditions and uncertainties that might not have been considered. It includes the group’s exploration of possibilities, with a give-and-take that adds richness and nuance that otherwise might be more difficult to achieve. Finally, the process can preempt surprises by anticipating developments before they occur...