Party competition in Western Europe is increasingly focused on "issue competition", which is the selective emphasis on issues by parties. The aim of this paper is to contribute methodologically to the increasing number of studies that deal with different aspects of parties' issue competition and communication. We systematically compare the value and shortcomings of three exploratory text representation approaches to study the issue communication of parties on Twitter. More specifically, we analyze which issues separate the online communication of one party from that of the other parties and how consistent party communication is. Our analysis was performed on two years of Twitter data from six Belgian political parties, comprising of over 56,000 political tweets. The results indicate that our exploratory approach is useful to study how political parties profile themselves on Twitter and which strategies are at play. Second, our method allows to analyze communication of individual politicians which contributes to classical literature on party unity and party discipline. A comparison of our three methods shows a clear trade-off between interpretability and discriminative power, where a combination of all three simultaneously provides the best insights.Electronic copy available at: https://ssrn.com/abstract=3782027 them an electoral advantage. Furthermore, the fragmentation of party landscapes across Europe in recent decades has increased the number of issues parties put forward. This explains why party competition in Western Europe has increasingly focused on the battle about which issues should dominate the party political agenda, i.e. "issue competition" (Green-Pedersen, 2007). The growing importance of issues in party politics, is also reflected by the rising attention for and proliferation of theories dealing with issue competition and communication (e.g. De Sio & Lachat, 2020).Traditionally, research would examine party manifestos, campaign ads or press releases to study strategic issue communication choices (Tresch et al., 2017). However, nowadays social media represents an interesting alternative, as it is perhaps the most widely accessible form of party communication, with higher temporal adaptability and interaction potential (De Sio & Lachat, 2020). There is growing scholarly interest in parties' issue communication and strategies on social media (Vargo et al., 2014;Van Dalen et al., 2015;Van Ditmars et al., 2020). However, the high volatility of social media communication in combinations with relatively short and less formal text complicates automatic coding methods and party-level analysis. Therefore, the main aim of this study is to contribute to the rapid increase of studies that deal with different aspects of parties' issue communication on social media.Especially Twitter is increasingly used by political parties and politicians to communicate with citizens, but even more so with opinion leaders and journalists (Jungherr, 2016;Vargo et al., 2014). We accept the press-release assumption of political pa...