This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book explores the dissolution of the classical project of sociological theory. The emergence of the classical sociological project coincided with the transformation of Western societies during the nineteenth century. The immediacy and thematic coherence of early sociology results from the visible presence of these changes: the founders of the classical project wanted to account for the transformation of the industrial-captialist/nation-state. Max Weber and Emile Durkheim retained many of the distinctive features of the classical project found in the works of Saint-Simon and Comte, but their audience and aims differed. Their theorizing continued to cover a broad range of social phenomena with political, economic and religious institutions the focuses of their theoretical works, and their empirical approach remained, for the most part, a comparative method sensitive to history.