Data4UrbanMobility co-organized the 4th edition of the PROFILES workshop on Dataset PROFIling and fEderated Search for Web Data at the 16th International Semantic Web Conference in Vienna, Austria on the October 22, 2017. The Web Data, including Linked Data, knowledge graphs and Web markup data is a rich and dynamic source of mobility relevant event-centric information. The PROFILES workshop series aim at gathering approaches to analyse, describe and discover data sources in Web Data as a facilitator for applications in mobility and further application domains.