The continuing transition toward open science is fundamentally changing both the ways in which scientists communicate research findings and what they communicate. Open science places emphasis on enhanced access not only to published research findings but also to pre-published literature (preprints), underlying research data, study protocols, and other products of the research process. This presentation will review the transformation in scholarly communication associated with open science and illustrate the ways in which libraries and other information service providers can support it, drawing on examples from the U.S. National Library of Medicine. Particular attention will be devoted to efforts to support open science as part of the ongoing response to the COVID-19 pandemic.