Abstract: The authors consider the issues of modern political and legal institutions functioning. The research subject is the processes of renewal and formation of political and legal institutions in their connection with social context (sociosphere). Special attention is given to three political and legal institutions of modern globalizing society - political parties, mass media and social organizations, associations and movements. The authors describe the stages of societies’ evolution and note the basic set of criteria and parameters which allow classifying countries according to the stage of their development. The authors consider the transformations happening to the above mentioned institutions in Western Europe and the U.S., i.e. the global core countries. The scientific novelty of the research consists in the revelation of contextual linkage when defining the effectiveness of functioning and vectors of transformation of political and legal institutions and their practices. The authors prove that the considered institutions are being transformed in accordance with the transformations in the authorities which more often use humanist ideas and permission methods instead of direct coercion. The authors note a complex impact of globalization and digitalization on the institutions of parties, mass media and social associations. The need for their analysis is determined by the rapid growth of their role in public life.