Comparative evaluation of cross-language information retrieval systems

With the increasing importance of the 'Global Information Society' and as the world's depositories of online collections proliferate, there is a growing need for systems that enable access to information of interest wherever and however it is stored, regardless of form or language. In recognition of this, five years ago, the DELOS Network for Digital Libraries launched the Cross- Language Evaluation Forum (CLEF), with the objective of promoting multilingual information access by providing the research community with an infrastructure for testing and evaluating systems operating in multilingual contexts and a common platform for the comparison of methodologies and results. In this paper, we outline the various activities initiated by CLEF over the years in order to meet the emerging needs of the application communities, and trace the impact of these activities on advances in multilingual system development.