The article examines the biography of Olga Pankratieva Teslenko (1911—1974), the eminent library scientist, developer and the first chief editor of the Library bibliographic classification (LBC). Her name is inextricably linked with the history of the national Library bibliographic classification and introduction of LBC in the practice of libraries.The purpose of the article is to reveal the significance of personality of the scientific supervisor in the formation of potential of sustainable development of the national classification system, ensuring its fundamental nature, comprehensiveness and integrity at all stages of the LBC development.The completion of publication of LBC schedules for scientific libraries (1960—1968) became an outstanding event in the national library science. Theoretical development of the LBC was most fully reflected in the Introduction to the Classification and in the numerous articles published in special periodicals. There were formulated theoretical and philosophical principles of LBC construction, substantiated the sequence of the main classes, the principles of classification of sciences. O.P. Teslenko has developed the priority table of LBC index signs for their automatic ordering. O.P. Teslenko made significant contribution to the study of issues related to the use of LBC as a language for automated information search. She carried out a lot of work on the analysis of LBC schedules in the light of the requirements of the automated information retrieval system (IRS) and developed the program of schedule optimization. As scientific supervisor, O.P. Teslenko created organizational structure for coordinating activity with the largest libraries of the country, their interaction with scientific and branch institutions and organizations cooperating in the development of the national classification.O.P. Teslenko’s articles on LBC, published in press, have found the response abroad, were translated into many languages and still serve as a source of theoretical and methodological basis in research studies on classification of sciences and library and information activities.