The Czechoslovak unified, all-in school, gradually built up in accordance with the Education Act of April 21,1948, setting up the groundwork for a unified school system, represents the first revolutionary stage in the development of the Czechoslovak socialist school. This school has changed the class basis of the Czechoslovak school dating from the period of the first bourgeois Czechoslovak Republic: it has changed the education system based on two separate types of education into a unified system enabling all children between the ages of 6 and 15 from urban as well as rural areas to attain lower secondary education in a compulsory primary and middle (junior secondary) school (5 + 4) and on this basis to proceed, without any blind alleys, with further education and attain perhaps even the highest forms of education. The author of this article goes on to characterise in detail the functions, the aims and the content of intellectual and moral education in the nonselective and selective Czechoslovak bourgeois school of the past, and the functions, the aims, and the content of intellectual and moral education in the unified school established under the Education Act of 1948, and by comparing them he demonstrates the change in the class basis of the Czechoslovak education system. In the next chapter the author takes a closer look at the struggle for a unified school, especially the efforts to overcome the conception of the so-called “streamed comprehensive school” which represented an attempt by the Czechoslovak opponents of the unified school to preserve class privileges in the field of secondary and higher forms of education for children of the former ruling social classes and groups, which were gradually being deprived of their positions of power. The author deals then with the subsequent development of the Czechoslovak unified school established in 1948. This development resulted from the needs and requirements of a socialist society to speed up and improve the training of qualified specialist, to deepen polytechnical and practical education at our schools, to make further progress in ideological and polytechnical education and the like. Attention is paid to the selection of pupils for selective senior secondary schools and for universities and other higher education establishments. Reasons are given for the principles underlying this selection. Basically, individuals with special talent for various fields of social activities (in science, in the fine arts, in manual, organisational, political work etc.) have proved to be equally distributed among all social classes and groups; interest in an all-round development of these talented individuals and the principle of the democratisation of education make it necessary for the social structure of the selective schools to correspond to the social structure of the contemporary socialist society. The author newly formulates some questions concerning the substance and relationship of intellectual and moral education, the unity of these two aspects of education in the process of communist education, then the problems of individual approach to pupils, the media and the conditions of communist education in a socialist society. In conclusion the author deals with the perspectives of further development of the Czechoslovak educations system on the basis of resolutions adopted by the 14th and 15th congresses of the Communist Party of Czechoslovakia, and the project of further development of this system. The conclusion arrived at by the Soviet school and pedagogy is confirmed for the conditions of education in the socialist Czechoslovakia: the implementation of general secondary education of the youth in the Soviet Union has proved in practice that the argument about the amount of the allegedly inherited limitations in the intellectual development of the individual — the argument which the bourgeois society uses in enforcing its class policy in education for the benefit of the ruling elite — is unscientific. Soviet science has countered this pseudo-scientific argument with the correct Marxist thesis on unlimited possibilities of man’s development under favourable social conditions.