In 2017, the government of Denmark appointed the world’s first tech diplomat to represent its interests before tech companies in Silicon Valley. Since then, various states and international organisations, including the United Nations (UN) and the European Union (EU), have followed suit. This has led to a rapid increase in the number of tech diplomats appointed worldwide. Despite the number of tech diplomats having grown rapidly in the past 8 years, the concept and practice of ‘tech diplomacy’ remain relatively unexplored in academic and professional circles alike. Through the practitioners’ insights and the analysis of empirical vignettes drawing from the EU, this paper explores the practice of tech diplomacy by identifying its key characteristics, players, processes, and objectives. The aim of this paper is to trace the contours of this emerging practice, contribute to scholarly understandings of how diplomacy is evolving during the so-called Fourth Industrial Revolution, and assess the broader impact of technological developments on international relations and global governance.