ode~rn politics is intimately linked to the politics of party systems. Ever since political parties made their appearance in the nineteenth century, most of the significant mass political activity in Western countries has been aimed at influencing the party system in some way: getting into it, getting control of it, maintaining it, overthrowing it, or replacing it. It is not surprising, therefore, that the modern study of party systems has been intimately linked to the study of democratic political stability and conflict resolution. The range qf the recent literature on party systems is extraordinarily wide. It includes the historical model-building effort of Lipset and Rokkan (1967), andDahl's (1966) broad comparative generalizations about oppositions. It encompasses the cross-national studies of Rose and Urwin (1970, 1969) and Blondel (1968), as well as the &dquo;theoretical case study&dquo; of Harry Eckstein (1966). Of even greater interest, in the context of this article, is the growing body of literature which examines the relations between party systems, social cleavages, elite behavior, and political stability in a particular type of political system