This paper investigates the systemic nature of methodological individualism. According to widespread belief, the notion of autonomy of the actor that is defended by methodological individualism is mistaken because it is incompatible with the study of society in terms of its organized structure. We argue that this viewpoint must be rejected. In our opinion, it stems from confusion between ontological nominalism – the idea that superhuman collective entities do not exist – and reductionism. In contrast, we would argue that methodological individualism is a form of nominalist structuralism. Following Hayek, Popper and Boudon, we will maintain that methodological individualism is not incompatible with the reference to systemic and irreducible properties. As these authors stressed, the history of methodological individualism is full of examples of non-reductionist explanations that undermine the widespread theory of the equivalence between methodological individualism and reductionism. We will state, therefore, that the current debate about methodological individualism is often based on a caricature of the concept of methodological individualism that does not match its correct meaning. In addition, we will provide a criticism of the notion of "structural individualism" that is becoming increasingly popular among social scientists.