The document summarizes the 4th Meeting of the Working Group on the pan-European open data Portal held in Spain on November 27th. It provides details on the Spanish open data portal datos.gob.es, including its main contents such as a data catalogue, training materials, and applications using PSI data. The portal sees high usage with 200,000 visits over 2 years and over 4,200 Twitter followers, and contains a catalogue of 116 organizations and 1,200 datasets. Upcoming improvements to the portal include a tool for cataloguing federation based on standards and a tool linking catalogues to provider information by December 2013.