In recent years, the world has witnessed the actions of various ultra-conservative and authoritarian leaders, governments and movements that challenge democratic institutions. The use of social media and tools for disinformation and the dissemination of fake news, including artificial intelligence applications, has been a common aspect in different national scenarios. From the national to the transnational, learnings and practices circulate, always with the aim of undermining principles, norms and experiences of democracy and of multilateral organisations. Through research that has resulted from a wide-ranging collective reflection conducted within LABMUNDO, the collection seeks to address this phenomenon from a theoretical and conceptual point of view. The different studies presented here consider the Brazilian context of the emergence of Bolsonaro and seek to analyse how ultraconservative and anti-democratic leaders and movements have produced negative influences on Brazilian foreign policy agendas.