In this paper, we present the system MULINEX, a fully implemented system which supports cross-lingual search of the WWW. Users can formulate, expand and disambiguate queries, filter the search results and read the retrieved documents by using only their native language. This multilingual functionality is achieved by the use of dictionary-based query translation, multilingual document categorisation and automatic translation of summaries and documents. The system supports French, German and English and has been installed and tested in the online services of two European internet content and service provider companies. This paper focuses on the techniques and algorithms used in the MULINEX system, explaining how each component works and how it contributes to the overall functionality of the integrated system. The primary system functionalities are outlined from the user perspective, followed by a description of the document database used in the system. The technologies and linguistic re...