By introducing the third section of the volume, Dissent as Regulation, this chapter explores the various meanings of the term dissent when used in a legal and technical context. Examining the different interpretations of the term, the chapter highlights a fundamental distinction depending on whether dissent is approached from a private or public law perspective. In private law, dissent is generally seen as something to be avoided, as it typically stems from a lack of understanding or agreement between the parties. In public law, however, dissent is often unavoidable and is thus regarded as an intrinsic element of the legal regime. This divergence in meaning reflects a broader dichotomy in the role of law. In the private law sphere, the law seeks to prevent and resolve dissent when it arises—typically in the context of a transaction. In contrast, within the public law domain, the role of law is different: it often involves seeking a “reasonable solution” when dissent emerges between public authorities or between individuals and the state.