The Stanford Encyclopedia of Philosophy (hereafter SEP) is a free online encyclopedia of philosophy run and maintained by Stanford University. Each entry is written and maintained by an expert in the field, including professors from over 65 academic institutions worldwide. Apart from its online status, the encyclopaedia maintains the traditional academic approach, used in most encyclopaedias and academic journals, to achieving quality by means of:

• the use of specialist authors
• selected by a editor or an editorial committee who is competent (though not necessarily a specialist) in the field covered by the encyclopedia
• the use of peer review.

The SEP has similar aims to such projects as the older Internet Encyclopaedia of Philosophy , and has rather different aims to wiki-based projects such as the philosophy pages here at Wikipedia. By several measures, such as by citation rankings, the SEP is easily the most successful and prestigious internet resource on philosophy.