Throughout their long history, socialists demonstrated a strong ability to review and adapt their doctrine, programmes, and practices to the changes in capitalism, politics, and society. Ideological controversies are an invariant of European socialist culture. This section examines continuities and changes within the socialist movement about the way its actors analyse the mutations of capitalism and conceive their actions, especially regarding the role of the state in some crucial moments. While it is certainly true that each socialist and social democratic party developed national peculiarities up until now, we argue these organizations increasingly converged towards similar positions when they come to deal with capitalism, democratic institutions, and the modern state.