Digital media have come to play an important role in the work of political parties and campaign organizations all over the world. Examples for the use of digital media in the United States (US) like Barack Obama's presidential campaigns of 2008 and 2012 and Donald Trump's campaign of 2016 dominate the public imagination. At the same time, it is important to recognize that the uses of digital media in politics vary considerably depending on campaign contexts or resources. This demands for the analysis of the use of digital media by parties and campaign organizations in varying temporal and international contexts instead of expecting the examples from the US to apply globally.The focus of this chapter lies on the discussion of how digital media have impacted the work of political parties, especially the way they run political campaigns. Political parties are at the heart of democracies and although they face persistent challenges regarding membership and public trust, they are crucial institutions connecting the people with political elites and the government (Dalton et al., 2011). This renders the impact of digital media on parties' ability to connect with voters one of the crucial channels through which digital media impact democracy (Jungherr et al., 2020, pp. 158-178).Digital media have a strong impact on politics beyond parties. They have changed the work of non-governmental organizations (Bimber et al., 2012;Karpf, 2012), extended the toolkits and repertoires available to activists and protestors (Bennett & Segerberg, 2013;Earl & Kimport, 2011;Jackson et al., 2020), and provided new forms of political participation (Theocharis & van Deth, 2018). These are important changes. But the specific institutional, organizational, and participatory characteristics of political parties deviate strongly from these other political organizations and forms of political participation. This makes the analysis and discussion about the role and impact of digital media in the work of political parties an important topic in its own right. Of course, this does not mean that the patterns identified in the broader discussion on the impact of digital media on political organization, participation, and activism do not also inform the study of political parties.By now, digital tools available to parties, elites, and people in their pursuit of politics and political information have reached a staggering variety. In the past, it was possible to discuss the role of 'the internet' in politics, 'social media', or specific services like Facebook or Twitter. Today, the variety of available services and their differentiated uses and functions challenges these unified approaches. Instead, I will use the term 'digital media' in order to capture the breadth of this phenomenon in the work of political parties. Here, I follow the