Mass gatherings (MGs) often bring together professionals and organizations that collaborate irregularly or have never engaged in joint working. They involve interaction and communication among multiple and diverse services, which can often prove challenging. Planning such an event is of paramount importance for its success, and interorganizational communication ranks among its most important aspects. Nonetheless, there is limited empirical evidence to support interagency communication in MGs.

This study used the 2017 Athens Marathon (Athens, Greece) as the empirical setting to examine how interorganizational communication was perceived among the multiple public health and safety professionals during the planning and implementation phase of the event.

Data comprised 15 semi-structured in-depth interviews with key informants, direct observations of meetings and the event itself, and documentary analysis. Open coding and thematic analysis were used to analyze the data.

Findings indicated three key components of interorganizational communication in such an event: (1) shared situational awareness; (2) interorganizational understanding; and (3) implementing liaison officers.

This study outlined the factors that influenced interorganizational communication before and during a MG. Practical implications arising from this study may inform the way organizers of marathons and other mass sporting events can engage in effective interorganizational communication.