Abstract Main topic of the course are computational lexicons, in particular the semantic layer, and their multifaceted relations with corpora. We will analyse existing semantic lexicons models, in particular the SIMPLE lexicons implemented for 12 European languages, with a comparison with the Wordnet lexicons. Different interrelationships between lexicons and corpora will be touched, and consequent research perspectives (e.g. for semantic annotation of corpora). The problematic issue of multiword expressions will be dealt with, also with reference to crosslingual problems. Finally current EAGLES/ISLE work on standardisation of multilingual lexical resources will be shortly discussed.