Abstract: Since the proposal of the open access S Plan in 2018, its influence has been expanding day by day, and the signing of the open access transformative agreements that actively responds to the S Plan has become a reality in many countries around the world. This paper introduces the main principles and implementation guidelines of the open access S Plan, and analyzes the progress and characteristics of the transformative agreements signed by various countries, as well as the important conversion measures of academic publishers under the background of the S Plan. In the global open access ecological environment, China should promote the establishment of relevant policies and mechanisms of open access, start the research on the content and terms of the conversion agreement, continue to promote and improve the construction of institutional repository, re-position the role of a library alliance, and introduce and cultivate professional interdisciplinary talents.

Key words: The Plan S, Open access, Library, Transformative agreements