This volume provides a multidisciplinary analysis of disinformation and strategies for tackling it. Authored by a diverse group of scholars and experts, chapters in this volume are divided into three thematic sections. The first section delves into disinformation from various disciplinary perspectives including philosophy, social psychology, economics, international law, data science, anthropology, political science and history. By examining the underlying factors behind disinformation and analyzing its impact on democratic processes, this section sheds light on its complexities, and reminds us that different policy responses are always grounded in different explanatory angles of the phenomenon. The second section focuses on the information ecosystem, investigating the processes, technologies, and actors involved in the spread of disinformation. By examining real-world examples and the roles played by different actors and technologies, this sheds light on the intricate workings of disinformation in different thematic and regional contexts. The book culminates in the third section, which focuses on crafting effective responses to disinformation. Chapters in this section explore policy efforts aimed at ensuring information integrity across the world, and highlight the importance of fundamental rights and evidence-based policy responses, encompassing self and co-regulation, quality journalism, fact-checking organizations and the pivotal role media literacy initiatives.