Scientific schools are alive by the standards of their creator: To the 120th anniversary of the birth of Academician M.A. Leontovich

This article is devoted to the life and work of the outstanding theoretical physicist, creator of world-famous scientific schools in radiophysics, plasma physics, and controlled thermonuclear fusion, Academician Mikhail Aleksandrovich Leontovich (1903–1981). His achievements in basic physics contributed to significant advances in applied research in many fields. The uniqueness of the scientific style and civic appearance of M.A. Leontovich, the lessons of his creative biography remain significant today, especially for young scientists, setting an example of selfless service to science.