Plan S is an innovative open access publication initiative under the direction of Science Europe, an alliance of funding agencies and research institutes across Europe. The initial plan was announced in September 2018 by Coalition S, an organization involving several institutions in Science Europe and some external institutions. The essence of the plan is that all the results of the researches funded by the agencies participating in Coalition S should be published in open access journals or platforms with no embargo period or posted to open access repositories. According to the plan revised last year, it will be implemented starting from January 2021. Coalition S currently includes national funding agencies from various countries in Europe, including France, the Netherlands, the United Kingdom, Sweden, Norway, Finland, Austria, Poland, Ireland, Luxembourg, and Slovenia, and private organizations such as the Gates Foundation and the Wellcome Trust. Plan S is also supported by the European Commission and the European Research Council. Participation is expanding to other continents and a wide range of research projects are expected to be covered by the plan, especially since all studies to be funded by Horizon Europe, the European Union\\u2019s large-scale funding program, will be targeted.
