In its World Energy Outlook 2020, the International Energy Agency predicts that renewable energy will more than double by 2030 for achieving global net zero emissions by 2050. Renewable energy is about to replace a significant proportion of fossil fuels, which are expected to decline by more than 35% compared to 2019. Under the same scenario, it is expected that 58% of car and light truck sales will be electric- and fuel cell-driven by 2030. Such developments would represent a significant reduction in CO2 emissions, while at the same time easily stored carriers become replaced with inflexible and geographically as well as temporally unevenly available alternatives. Such a transformation puts the existing electrical energy system under stress and requires an increasing degree of capacity and flexibility, both short-term and seasonal, at regional, national and international levels. From October 19 to 20 2020, 78 experts from industry, administration and academia discussed for the fourth time the effects, prospects and solutions of grid services for a transforming electricity system. With 15 scientific papers and 17 invited presentations, the symposium dealt with market developments, international cooperation, operation and enabling technologies, virtual power plants and flexibility providing technologies. The European perspective on energy transition and the flexibility roadmap were delved into along with national perspectives for the implementation of harmonized grid services markets, where their orientation and implementation also took account of national circumstances. Expanding flexibility products, digitalization, risk hedging and advanced market design were pointed out as ways of increasing market liquidity. Crucially as important, improved weather and load forecasting algorithms for reducing the balancing gap was covered. With Corona influencing the way people met, the symposium had to be transferred to a virtual space at short notice. Although questions to the speakers had to be asked in the live chat room, no quality and quantity compared to previous years was lost. The discussions between the participants took place in break-out sessions, where personal contacts could be made. Despite travel restrictions, a very diverse and valuable exchange between experts from industry, administration and science could ultimately still take place. This gives the base and the motivation to reorganise the growing Grid Service Market symposium. Due to the shift of GSM 2020 in to autumn, the GSM 2021 will be a shorter, attractive reunion of the experts also in autumn. However, GSM 2022 is planned to be a fully physical networking and exchange event in summer in Lucerne again. Naturally the virtual attendance will be one of the new features allowing participating from all over the world, when travelling is restricted due to any reason. Enjoy now the proceedings of GSM 2020 and seek for upcoming releases.