A guide to Plan S: the open-access initiative shaking up science publishing

In 2018, an influential group of research funders announced a bold pledge: the scientists they fund should publish their peer-reviewed papers outside journal paywalls. The initiative, called Plan S, caused an instant uproar over its aim of ending journal subscription models — the means by which many scholarly publications have financed their existence. Its intended start date in 2020 was delayed, and its details were tweaked. But after much sparring over policy, the project formally began in 2021, with 25 funding agencies rolling out similar open-access (OA) mandates.