This presentation reports the methodology followed and the results attained on an on-going project aiming at building a large lexical database of corpus-extracted multiword (MW) expressions for the Portuguese language. MW expressions were automatically extracted from a balanced 50 million word corpus compiled for this project, furthermore statistically interpreted using lexical association measures and are undergoing a manual validation process. The lexical database covers different types of MW expressions, from named entities to lexical associations with different degrees of cohesion, ranging from totally frozen idioms to favoured co-occurring forms, like collocations. We aim to achieve two main objectives with this resource: to build on the large set of data of different types of MW expressions to revise existing typologies of collocations and to integrate them in a larger theory of MW units; to use the extensive hand-checked data as training data to evaluate existing statistical lexical association measures.