Class actions in privacy law are rapidly growing as a legal vehicle for citizens around the world to hold corporations liable for privacy violations. Current and future developments in these class actions stand to shift the corporate liability landscape for companies that interact with people’s personal information. Privacy class actions are at the intersection of civil litigation, privacy law, and data protection. Developments in privacy class actions raise complex issues of substantive law as well as challenges to the established procedures governing class action litigation. Their outcomes are integral to the evolution of privacy law and data protection law across jurisdictions. This book brings together established scholars in privacy law, data protection law, and collective litigation to offer a detailed perspective on the present and future of collective litigation for privacy claims. Taking a comparative approach, this book incorporates considerations from consumer protection law, procedural law, cross-border litigation, tort law, and data protection law, which are key to understanding the development of privacy class actions. In doing so, it offers an analysis of the novel challenges they pose for courts, regulatory agencies, scholars, and litigators, together with their potential solutions.