Concepts of virtual libraries and their integration within the Europeana project. Fragility of digital data as a challenge for CASPAR project. Custodea as open source initiative for efficient solutions in the cultural sector. Europeana, CASPAR and Custodea as a follow-related community projects. Project Custodea will be presented - www.custodea.sk: Custodea as logical and technological support for Europeana and Europeana Local based on principles set out in the CASPAR project. Solutions Custodea for "memory" institutions - galleries, museums, libraries, etc. Custodea solutions covering digital data and metadata harvesting, transformation and conversion, retrieval, storage, presentation and content delivery - for Europeana as an example.