Encyclopaedia Britannica is to let readers edit its entries.
From next week, visitors to the publication's website, Britannica.com, will be able to submit proposed changes to editors, who will check them and make alterations if they think they are appropriate.
The company said in a statement on Friday that users whose suggestions are accepted will then be credited on the site.
The authoritative reference book was first published in 1768. It is battling to keep pace with internet competitors like Wikipedia, which is free.
The Times reports that Britannica.com attracts 1.5 million visitors per day. Wikipedia attracts roughly six million.