About Science Express

What is Science Express?
Science Express provides rapid electronic publication of selected research papers, Perspectives, and other articles that have recently been accepted for publication in Science. Each week we select several papers for online publication in PDF format within two weeks of acceptance. For authors, it's a chance to get their peer-reviewed results in front of the scientific community as much as four to six weeks before they would otherwise appear in print. For readers, it's an opportunity to connect with these hot results immediately.
What's the "official" publication date of a Science Express paper?
Science Express papers are considered to be published on the day they are posted, and are citable from that date. The online publication date appears in the print version of the paper.
How are Science Express papers chosen?
The editors select the papers appearing in Science Express from among all fields of science. The main criteria are the timeliness and importance of the research. Additional editorial changes in the text and figures may appear in the print version of the paper.
How do I get Science Express?
Access to Science Express papers is free to AAAS members as a benefit of membership -- as is all content from Science. Simply click on the content you want and enter your user name and password. Other individuals who aren't AAAS members can access through a pay-per-view option. (Further information on membership is available here.) If you're accessing the site through a university or other institution, your institution may also have access to Science Express; it's available as an optional add-on to our institutional site license subscriptions.
I can't access Science Express papers at my institution's library -- what's going on?
Even if your institution subscribes to the full-text version of Science Magazine online, it may still not have access to Science Express papers until they are published in print. Full-text access to Science Express papers before print publication is available as a premium add-on to the standard Science site license. If your library doesn't have access to Science Express and you think your work could benefit from early access to these hot research results, speak to your librarian or use our Web form to recommend a subscription to your library.
What happens to Science Express articles when the print version is published?
When the print version appears, the Science Express version is replaced with an electronic file of the print version, and the paper is moved to the appropriate print issue on the Science site. The paper will no longer appear in the Science Express index; however, all links and bookmarks will still access the final printed version (the URL will not change). Access to the earlier Science Express version of the paper is available through a link from the full text of the online version of the final print paper; the digital object identifier (DOI) of the paper, which allows rapid electronic access to all versions, also appears in print.
How do I cite Science Express articles?
Papers posted in Science Express are considered published on the date that they are posted. The print version of a Science Express paper indicates the date when the paper was published online and gives access and citation information. Please cite papers that have been published in Science Express as follows:

In citing a paper that has been published in Science Express but has not yet appeared in print, include the name of the journal Science, the date, and the DOI in the citation -- for example:

W. Jones, B. Smith, Science, 20 December 2005 (10.1126/science.1054678).

After print publication of a Science Express paper, include the full print reference, the date, and the DOI of the electronic publication -- for example:

W. Jones, B. Smith, Science311, 496 (2006); published online 20 December 2005 (10.1126/science.1297580).