IIR 2013 is the 4th edition of the Italian Information Retrieval Workshop. It will take place at the National Council of Research campus ("Area della Ricerca del CNR") in Pisa, Italy, and will be jointly organized by the Institute for the Science and Technologies of Information (ISTI) and the Institute for Informatics and Telematics (IIT) of the Italian National Council of Research (CNR), Pisa.