Organizational improvisation is often enacted as a response to an unexpected disruption or sudden change, comprising an integral element of sensemaking. When the improvisational trigger occurs, several processes are set off which may also comprise several periods of the improvisational process. In this chapter. we identify three periods that fall within the framework of influence of the improvisational process which, as a whole, we termed the improvisational arc. Each of these periods corresponds to a different phase of improvisational sensemaking. Right after the trigger, organizational agents have to ponder the potential improvisation and decide on its implementation. This improvisation decision period corresponds to the improvisational decision sensemaking phase. Once the decision is made, the improvisation period begins, which corresponds to the improvisational action sensemaking phase. When improvisation ends, a period of improvisation aftermath is initiated, which corresponds to the improvisational retrospective sensemaking phase. Based on Weick's theory of sensemaking (1995), this chapter addresses the different characteristics associated with the different phases of the improvisational sensemaking process along the improvisational arc. The chapter contributes to the improvisation and sensemaking literatures. By taking the perspective of the seven characteristics of sensemaking proposed by Weick, it allows for an in-depth look at the different periods of the improvisational arc in order to better understand how the meaning of emergent reality is constructed, and how this construction takes various forms throughout the different phases of improvisational sensemaking.