Abstract: This is a major piece of work that forms the baseline with which to compare the more detailed case studies. It sets the terms of the debate in that it indicates that there has been a decline in levels of class voting in certain countries but not in others. It also addresses certain social structural explanations of these variations, which focus on cross-national variations in the changing composition of classes. The elaboration of national variations in the extent of continuity in class politics is then pursued in more depth in the detailed case studies that follow.