Finally, after three years of anxious waiting, the long-awaited CIGRE Centennial Session began its work! The new virtual format allows participants from around the world to save a significant amount of time and money by combining participation in the session with daily work, as well as to communicate fully with colleagues from other countries, despite the continued restrictions of COVID-19 pandemic. "ELECTRIC POWER. Transmission and Distribution" journal, as an official media partner of the Centennial Session, will provide coverage of all the most significant events of the Session. Given the new format of the Centennial Session, its programme was adjusted. The time for virtual meetings was chosen in such a way that specialists from all over the world were able to participate in those meetings: for some, it is earlier in the morning, for others, it is working hours or evening. Because of this, organizers decided to reduce the time of daily discussions by 2-3 hours, while expanding the dates of the Centennial Session from the traditional 6 days to 10 days. Active collaboration of world experts began on August 18 on seven virtual discussion platforms simultaneously. Before all panel discussion and webinars started, Michel Augonnet, CIGRE President, and Philippe Adam, Secretary General, addressed the delegates. Delivering their welcoming remarks, CIGRE leaders praised the high interest of specialists around the world in the Virtual Centennial Session: despite the virtual format, experts from more than 60 countries take part in the event. Michel Augonnet and Philippe Adam also noted a large amount of experience gained by electric power experts and issues that needed to be discussed among the delegates: more than 800 papers were submitted to CIGRE-2021. The virtual platform of the Centennial Session is designed to fully replicate the usual structure of a CIGRE session, including 16 new tutorials, 4 major workshops and 16 interactive conferences of CIGRE Study Committees. Using the multifunctional desktop, participants have the opportunity to see representatives of the Study Committee on the topic of the discussion, the speaker, presentation slides, as well as online chat, which allows both asking and answering questions. It is possible to switch the desktop formats as a convenience to focus on either the speaker, presentation slides or chat. The newly created CIGRE-TV provides additional opportunities to witness everything as if you were there. Operators, as far as possible, show online participants various conference halls and rooms of the Palais des Congrès in Paris where CIGRE-2021 face-to-face participants gather. The technical exhibition, which is traditionally held as a part of a CIGRE session, is also available for all participants in virtual format. Electric power experts have the opportunity to learn about products and solutions from more than 70 producers from 24 countries and virtually communicate with their representatives. On the first two days of the Centennial Session, the following topics are being discussed during five virtual sessions and four webinars: B4: DC systems and power electronics; C5: Electricity markets and regulation; B1: Insulated cables; C1: Power system development and economics; B2: Overhead lines; A1: Rotating electrical machines; D2: Future operation of electric power transmission and distribution systems under further enhancement of data exchange; A2: Assembly, repair and high-voltage testing of power transformers at the facility; A3: DC switchgear design for transmission and distribution systems. The Opening ceremony of the CIGRE Centennial Session will be held on Friday, August 20. After the Opening ceremony, an extensive discussion on the future development of energy systems will take place, while at the same time there will be other technical events within the framework of CIGRE-2021. "ELECTRIC POWER. Transmission and Distribution" journal will continue to provide coverage of all significant events during the Centennial Session.