The Text REtrieval Conference is a workshop series designed to encourage re
search on text retrieval for realistic applications by providing large test
collections, uniform scoring procedures and a forum for organizations inte
rested in comparing results. TREC contains two main retrieval tasks plus op
tional subtasks that allow participants to focus on particular common subpr
oblems in retrieval. The emphasis on individual experiments evaluated in a
common setting has proven to be very successful. In the six years since the
beginning of TREC, the state of the art in retrieval effectiveness has app
roximately doubled, and technology transfer among research labs and between
research systems and commercial products has accelerated. In addition, TRE
C has sponsored the first large-scale evaluations of Chinese language retri
eval, retrieval of speech and retrieval across different languages. Publish
ed by Elsevier Science Ltd.