I seriously doubt that there exist many physicists in the world today who do not have at least a few of the volumes of the Landau-Lifshitz series Course in Theoretical Physics in their personal libraries. There are many reasons for the enormous popularity of these books: the wide range of topics covered, the presentation of the material in a lucid and decidedly nonpedestrian manner, the fact that many important advances in theoretical physics were due to L. P. Landau and his coworkers, and, certainly, the fact that if one has a very intelligent question about some point of physics one is likely to find that question discussed and answered somewhere in the Landau-Lifshitz books.