Chapter 2 discusses the historical and methodological roots of the social psychology of protest, illustrated with meta-analytical data. Social psychology has evolved through two branches, in psychology and in sociology. These clearly differ regarding the level of analysis, basic assumptions, method, and areas of research in studying protest. The roots of the sociological branch are European, contextual, comparative, and non-positivistic. The roots of the psychological branch originate in the United States, where the behavioral and experimental approach dominated. These disciplinary roots are not without consequences for employed methodologies. Sociological social psychologists use shared social knowledge from a macro- or meso-level culture to explain relatively enduring patterns of symbolic social interaction, investigating with qualitative methods, such as discourse analysis, event analysis, interviewing, participant observation, case studies, and network analysis. Psychological social psychologists, alternately, typically look at what leads us to behave in a given way in the (imagined) presence of others, and the conditions under which certain behavior/actions and feelings occur. In general, they have a preference for laboratory-based, empirical findings. Each method has its own strengths, weaknesses, and challenges. We will discuss studies conducted, present illustrative findings from such studies, and indicate the strengths, weaknesses, and challenges of the method.