Multiple Streams Analysis

The problem stream is the set of conditions that come to be recognised as public problems, brought to attention by worsening indicators, focusing events or feedback. The policy stream is the continually churning pool of ideas and proposals generated by policy specialists. The politics stream consists of the national mood, election results, partisan balance and organised interests. Kingdon's central claim is that these flow largely independently, and that significant change requires their coupling during an open policy window.

A policy window is a transient opportunity for advocates to push their solutions onto the agenda, opened either by a pressing problem or by political change such as a new administration. A policy entrepreneur is an actor — inside or outside government — who invests time and resources to exploit such windows by coupling a ready solution to the live problem and the favourable politics. Windows are short-lived, so entrepreneurs must be prepared in advance and act quickly when one opens.

Only weakly. Because it foregrounds ambiguity, timing and the somewhat unpredictable opening of windows, the framework explains why change occurred at a given moment far better than it forecasts when change will happen. Its concepts are also metaphorical and loosely defined, which makes precise prediction and falsification difficult. It is therefore most powerful as a structured lens for retrospective explanation of agenda setting rather than as a forecasting tool.