Academician Otokar Chlup’s interest in the problems of the Basic School has been the Cardinal point of his scientific and constructive work on the system of Czechoslovak education ranging from nursery school to university. In the period before World War I he worked hard on educational pre-requisites of lay education. He understood lay education not as being isolated within the frame- work of a subject, but he aimed at laicization of the whole system of education and schooling at the state school with compulsory attendance. While teaching at the Brno University he established an experimental class for talented pupils in the 4th and 5th year; this class was attached to the pedagogical seminar. The results of the experimental teaching were applied especially to the language teaching process, in which he applied a rational system of teaching grammar. At that time he carried out ≫A research into the manifestations of less capable children’ confronting them with the manifestations of normal children a talented ones. When in Prague, he organized, with the help of Zdeněk Nejedly, Minister of Education, university education for teachers at the Pedagogical Faculty of Charles University. He saw to it that, besides didactic preparation, teachers were given proper professional training in science and arts. In the most recent period, when he was charged with building up the Educational Institute of the Czechoslovak Academy of Sciences in Prague, he promoted, in connection with the textbook theory, also the hypothesis of basic subject-matter specified according to the elementary and secondary stage of education at the Basic Nine-Year School. The results of the researches in this period led Chlup to create the pre-requisites tor such a didactic system, in which the leading components would not be exclusively psychological and formally logical aspects, but the new integration of the basic subject-matter, which is of primary importance for educational practice as well as for the theory of education.