This chapter discusses how the results of the text analysis can be exploited in a retrieval context. Transparent Information Retrieval (TIR) describes a multilingual setup where query and result presentation are given in the user language while the documents may be written in different languages, this fact however being transparent to the users. Obviously two translation steps are required for this.The resource proposed is a dynamic multilingual concept net, i.e. an index enriched by links between terms on both monolingual (synonyms, head-modifiers) and multilingual (translations) level. The difference of the LtConceptNet to thesauri, multilingual WordNets, and ontologies is explained, its layout is given, and its use in query expansion and translation contexts is explained by two application examples.