Advances in technology have triggered the emergence of a new generation of science communication forms that are based on Open Science (OS), an umbrella for different movements whose goal is to promote transparency, reusability and connectivity of research. It provides the infrastructure (platforms, tools and services) to make scientific information freely available. OS can mean many different things—open access to publications, open research data, open peer review, open citations, open-source software, open collaboration, open notebooks, open educational resources, open books, and citizen science. This chapter focusses on the movements promoting (1) Open access to publications, (2) Open peer review, (3) Open research data, and (4) Open access to citations. It also looks at how preprints, academic social sites, and new communication formats, such as Registered Reports, Lab Protocols, and Study Protocols, are challenging the traditional scientific publishing system.