Virtualization is a key technology that helps to combine applications on various platforms and hardware of previous generations using a smaller number of modern, more powerful servers with low power consumption.... Currently , Possibilities, offered by this technology, can be significantly expanded by using it to meet the needs of multi-level data storage (storage virtualization) as well as for the so-called virtualization of client places , which provides the user with access to working materials from any terminal , Including remote locations..................................... The article deals with virtualization of all levels of IT infrastructure: servers, storage systems, client workplaces, data center infrastructure. Approaches of various manufacturers to solving problems and implementing virtualization technologies are considered. The material was prepared within the framework of the All-Russian competitive selection of review and analytical articles on the priority direction "Information and telecommunication systems" (http://www.) ict. edu. en/itkonkurs2008/)