The concept of cleavage plays an important role in the literature on party system formation and contemporary voting behavior studies, as Martin S. Lipset and Stein Rokkan have stated in their “cleavage theory”. The definition of divide is divided by a sort of existence of demographics and stable or aligned attitudes and conflicts within the structure of society.The general opinion is that voters do not come in predefined groups. Cleavage divides voters by two: lawyers and opponents on a certain subject, or vote for a certain party.According to Lipset and Rokkan, modern party systems are defined by historical conflicts and the lasting identities created by the interaction of these conflicts and social institutions that can explain national variations in party systems. The influence of traditional social divisions has decreased in the choice of the individual vote. This raises the question of whether such cleavages can still be powerful in the structuring of parties and their systems? Can we ask if this theory is still acceptable in the new democracies?First, I will explain the formation of party systems with a theory of cleavage according to Rokkan’s ideas and also important cleavages according to him. In the second section, I will explain why cleavage theory can help us understand what has happened in the new democracies and some contemporary uses of the concept of cleavage in new democracies with the examples of Western European countries. At the end of the dissertation, I will examine the spatial scope of the model taking into account the recent evolutions as well as various aspects and the durability of the model.There are different divisions in society, but Lipset-Rokkan has defined four fundamental cleavages for Western civilization. According to them, these divisions have determined the emergence and the content of many political parties, especially in Europe. With the emergence of two revolutions, the national revolution and the industrial revolution, different social divisions related to the division of parties and electoral behavior were created.The first revolution, the National Revolution, resulted in a center-periphery conflict between the national culture and the matched subordinates. The periphery of the city center can be explained by a conflict between elites in urban areas and those in more suburban areas. This is usually expressed in terms of regional nationalism. This separation is caused by the creation of modern nation states, where some states were better than others in assimilating other cultures to the majority nation. The Church-State tension between the state, which sought to dominate, and the Church, which tried to maintain its historic corporate rights, caused problems. State versus church means conflict between religious and secular voters.The second revolution which is the industrial revolution has led to a cleavage of the land industry between the land elite and the growing bourgeois class or between capitalists and workers. Owner versus worker signifies a cleavage of class This cleavage has resulted in the formation of parties of the left and parties of the right. It is sometimes said that this cleavage represents a conflict between the rich and the poor. Land in relation to industry can be explained by the exercise by the State of the control of tariffs, against the freedom of control of industrial enterprises.The national revolution that refers to the process of formation of the nation-state and the industrial revolution that refers to the construction of external borders have been crucial prerequisites for internal political structuring. A sectoral division between the first and second sectors of the economy is opposed to agricultural and industrial interests. The class divide was not the strongest but it has come to structure politics in many countries.These four cleavage sources that I have explained have continued to some extent in the contemporary world. And they produced a framework for party systems of democratic regimes. The dual processes of national and industrial revolutions constituted “critical moments” and led to long-term alignments between social groups and political parties.The Western world seems to have entered a new political phase in the mid-1960s with the emergence of post-materialist issues such as a clean environment, the use of nuclear power, a better culture, an equal status for women and men. minorities, the quality of education, relationships, larger democracies, family and sexual issues. These have been perceived by some social analysts as the social consequences of a new emerging “revolution”, the post-industrial, which introduces new bases of social and political cleavage. However, the problems and cleavages derived from those of the industrial society remain more important sources of political division and electoral choice, since the most materialistic workers and the self-employed. When these postmodern conflicts made their way onto the political agenda of industrial democracies, the links between social groups and parties on which the established structure of the old conflicts is based were weakened. The long-term evolution of the social structure weakens the hold of established divisions. The system reflecting mainly old conflicts – religion, nation – will be less rooted in the social structure than a few decades ago, opening a window of opportunity for potential emerging conflicts. For example, in some Western European countries of the 21st century, a new cultural divide has emerged, calling into question the old old political cleavage over economic conflicts. This transformation has occurred since the mid-1960s, with the New Left born at that time of libertarian and universalist values, and a right-wing populist reaction, born in the 1980s with traditionalist and community traditions.After communism in Eastern Europe, it seems that the application of Western European case theories to the new party systems of Central and Eastern Europe is relevant. Cleavages, institutions, voting systems and, to some extent, party organizations have combined to create a framework that reinforces the importance of how parties have chosen to compete. The competitive development of multi-party systems in Central and Eastern Europe was motivated by the conflict between parties to define the post-communist “right”. Also in the European Union, the cleavage theory has defined the positioning of national political parties. Political parties have much more in common with parties of the same family than other parties in the same country. The reason for this is that parties are shaped by their distinct historical experiences, the most influential of which are the ideological propensities and constituency ties that derive from the basic divides that structure contention in a society. The differences between the different political parties on European integration can be explained by territorial differences in the historical interaction of the cleavages between countries and regions. In short, a theory of the cleavage of party positioning makes it possible to understand the variations within party families as well as the variations between them.Organizations that have linked voters to parties – including churches for faith parties and unions for socialist parties – include a smaller share of the population. The attributes of life that structured political preference – social class and religion – have lost their predictive power. But these developments do not exhaust the theory of cleavage. The power of formation of certain cleavages diminishes with time, but few die completely. Territorial cleavage, religious cleavage and class division have lost their power, but none has been extinguished. The cleavage theory conceives layers of partisan attachment rather than the replacement of one dimension of challenge by another. The class division, rooted in the industrial revolution, produced the main socialist parties in all fields.The evolution of many systems confirms the classical sequence of European cleavage formation with the initial and decisive emergence of territorial and cultural identity cleavages, followed later by the appearance of economic cleavages. The decline of traditional divisions does not necessarily mean the end of the structuring of politics by social divisions. The four-cleavage model ceases to be relevant to the United States, many Third World countries, and some old democracies. But I believe that the formation of divisions in the world is starting to change and the Lipset-Rokkan model is no longer applicable to certain countries (especially in Eastern Europe). The Lipset-Rokkan model is more applicable for western European countries, especially because of the different economic and political development, the model is still useful nowadays. The Lipset and Rokkan four-cleavage model would be enriched by a little more recognition of complex situations.