The chapter substantiates the need to use digital twin technologies in decision-making at all stages of the life cycle of a high-tech product (strategy developing, R&D managing, construction) and at different levels of management (intersectoral, industry, corporate, and engineering). It is proven that, with the growth of the level of management, it is necessary to consider more and more extensive systems and to take into account a wider range of factors of various natures (physical, technical, technological, economic, environmental, social, political, etc.). The authors analyze the types of management tasks in modern high-tech industries and the significance of what experience and abilities highly qualified managers have (in contrast to mathematical modeling and digital twins), and furthermore assess whether the experiences of Soviet engineers and designers from the aviation and space industry are applicable in this area. The reasons for the low demand for digital twins in the Russian high-tech sphere are investigated. Examples of erroneous decisions at various levels of management—and the losses caused by them—are given.