An embargo is an information subsidy in the form of an agreement between a news source and a journalist under which the source gives the journalist access to information before it is given to the public, and in return, the journalist agrees not to disseminate news about the information until a designated day and time.

Embargoes are used throughout journalism. However, they are particularly prevalent in journalism about science and technology—most [Page 250]commonly, in news about research published in major journals—because of the combination of the perceived difficulty in reporting on these topics and the control that the scientific establishment can exert over access to information.

For example, the journal Science is published on Fridays. However, selected journalists are allowed to read advance copies of papers in ...