ALTHOUGH THE CLASSICAL WORK ON POLITICAL OPPOSITION IN Western Democracies, edited by Robert Dahl, was published decades ago, in 1966, the analysis of the characteristics of opposition, in democracies or elsewhere, has advanced rather less than other aspects of comparative politics. The word ‘opposition’ is used daily to account for a variety of developments; but its many meanings have not been systematically related to the differences among the political systems of the world. A number of comparative studies did appear after the 1966 seminal work, admittedly, including one by Dahl himself in 1973, as well as those by Ionescu and Madariaga in 1968, by Schapiro in 1972, by Tokes in 1979, by Kolinsky in 1988 and by Rodan in 1996; these volumes explore aspects of the concept which could not have been even referred to in the original study, since that study was confined to Western democracies and to the part played by political parties in the context of opposition. Yet the problem has still not been tackled truly comprehensively, as, with the exception of the 1973 Dahl volume, the works on the subject are comparative only in the sense that they deal with more than one country; but their scope remains limited to a region or to a particular type of political system. Meanwhile, many country analyses examine the nature of political opposition in each particular case, but the information which they provide has to be brought within a common framework before we can hope to obtain a general picture of the characteristics of opposition across the world.