The focusing event theory has been substantially formed by contributions of John Kingdon by offering a somewhat broader definition of focusing events through the prism of his multiple streams theory, and Thomas Birkland, who introduced better precision by listing a number of basic characteristics of focusing events (eg using the example of 9/11 terrorist attacks as a focusing event, as in Birkland 2004). These major contributions notwithstanding, there still seems to be a strikingly persistent absence of clarity in defining the notion of" focusing events" within the agenda-setting stage of the policy process, and a lack of a general typology of related significant, or key events. Even somewhat more disturbing is that, inspired by Birkland’s notion of focusing events, a number of subsequent scholars attempted to develop this theory, unintentionally further conflating the meaning of focusing events.
