An open access option for PNAS.

Arevolution is taking place in scientific publishing. To leverage the tremendous advantages of electronic publishing and the Internet, journals such as PNAS are making the scientific literature more freely available online than ever before. PNAS has already done the following: 1. We are making PNAS free online to everyone around the world. By the end of this year, all content should be free from the first volume in 1915 to articles published just 6 months ago. The articles will be on our web site (www.pnas.org) and on the National Library of Medicine's PubMed Central (www.pubmedcentral.nih.gov). 2. We have made PNAS content free online immediately upon publication to 145 countries that are struggling to develop their scientific infrastructure. The list of countries is available at www.pnas.org/misc/faq.shtml. 3. We have changed our copyright and permissions policy to make it easier for authors and readers to freely use material published in PNAS for educational purposes. PNAS now allows authors to post the PDF of their article on their web site, to post and update preprints, and to post webcasts. Anyone may reuse original figures and tables published in PNAS for educational purposes without having to request permission. In this Editorial, we announce an experimental open access …