In this study, we investigate the communication behaviour in Twitter during the rise of a corporate crisis. In September 2015, the emission scandal of Volkswagen (also known as "Dieselgate") became public. We collected Twitter data and analysed approximately 400,000 tweets regarding the Volkswagen crisis. We take different perspectives on the data, by 1) separating the overall communication in peak and quiet phases, 2) analysing the sentiment in each phase, 3) looking at specific tweet contents, and 4) using statistical analyses to determine the significance of differences. Furthermore, we mapped the publishing behaviour of official Volkswagen accounts to the situational crisis communication theory (SCCT). The findings suggest that Volkswagen followed a strategy that is not covered by SCCT, i.e. keeping silent. Volkswagen's tweets were not able to reduce the emotionality and sentiment of the ongoing Twitter discussion. Instead, even during quiet phases, the communication remained rather negative. companies develop and adjust communication strategies for improving the company's image and diminishing the impact of a crisis situation [6]. For companies it is getting increasingly important to learn how to react on social media during crises, because it might affect their reputation and market position seriously and permanently [43]. Crises-related communication is often highly recognised and strongly discussed in social media, resulting in peaks, emotional expressions, and information sharing. While there is already some understanding of the general dynamics of social media crisis communication, there is little knowledge about how companies behave during a crisis and if they are able to affect the communication and users' attitudes [23,35]. Based on the possibility to easily and quickly share a message with a potentially large audience, people frequently use online social media to communicate about crisis events [40,44]. The emerging importance of social media and its utilisation is therefore affecting the way how companies need to behave during crises [34].In this paper, we investigate the Twitter communication that was generated during the rise of the "Dieselgate", which was a scandal of global scope and Volkswagen was threatened by litigation in many countries. The global scope of this scandal represented a threat to VW's performance. This case exemplifies the more general question of how emotionally charged discussions can diffuse through microblogging during scandals that can carry substantive performance implications. Even though some case studies on crisis communication in social media exist [38], there is still little understanding about how companies react in such situations. Therefore, in this case study, we provide and analyse empirical data to understand corporate behaviour during a global crisis situation. Our study is guided by the following research questions (RQ):RQ1a: How do Twitter users communicate in the rise of VW's "Dieselgate"? RQ1b: How can the Twitter communication behaviour of VW during a ri...