Europeana gathers millions of metadata records from over 3500 libraries, archives and museums across Europe. Such a diversity with many quality issues (sparseness, heterogeneity, multilinguality). We present how Europeana and its partners work to address these issues, in a collaborative and flexible fashion. The Europeana Data Model paves the way for gathering richer metadata, but all parties need to exploit this potential. Especially, populating the data model's elements with multilingual linked open data vocabularies can bring a lot of value. We encourage our partners to publish richer metadata that exploits the controlled vocabularies they often already use. We also perform automatic metadata enrichment, using a purpose-built linked-data based "entity collection" as target. Finally, partners have also embarked on producing their own automatic metadata enrichments. In parallel, the Europeana network has developed a tier system for the Europeana Publishing Framework, which enables measuring and reporting on important aspects of metadata quality in the Europeana datasets.