During the past twenty years political protest has become increasingly frequent in industrialized societies. At the same time the literature on social movements and political protest has grown rapidly too. Numerous empirical studies on various kinds of movements, citizen action groups, and protest events have been conducted, on the micro as well as on the macro level. In the 1970s the “classical” model for explaining these phenomena, which emphasizes individual motivational factors such as anomie, social isolation, status inconsistency rising expectations, and relative deprivation, came under attack, and a new group-oriented explanatory model, resource mobilization theory, became the dominant paradigm. One possibility for gaining new insights into social phenomena is to apply a general social theory. Rational choice hypotheses about political protest are only one group of hypotheses intended to explain protest. The chapter also presents an overview of the key concepts discussed in this book.