Mistrust in the 21st century is a major societal concern. This book: - explores social psychological processes that explain why and how mistrust develops - considers the effects that it has upon those who are mistrustful and those who are mistrusted - offers a model of mistrust in individuals and communities which is based on theories of identity and social representation. With examples ranging from the the 1872 US presidential election to the Trump era, it also considers Brexit, and has a significant focus on the Covid-19 pandemic. By looking at the role of social media, and how mistrust can be weaponised this book interrogates its place in our society. Ultimately, whilst feeling mistrust is part of being human this book warns that we ignore mistrust at our peril. Dame Glynis M. Breakwell is Professor Emeritus at the University of Bath in the Department of Psychology and has Visiting Professorships at Imperial College, London, University of Surrey and Nottingham Trent University.