"Personal Information Management (PIM) is an activity whereby people store their personal information to retrieve it later. Many millions of computer users retrieve their files several times a day, so improving this process will significantly improve personal and corporate productivity. Prior work by Dr. Bergman in his initial Marie Curie Fellowship indicates users often have poor organizational strategies for personal information making retrieval difficult. This will not be addressed by improvements in desktop search, as that work revealed a strong preference for navigational access strategies using folders rather than search. However the precise relation between organization and retrieval in PIM has not been systematically studied to date. This project will therefore study the relation between organization and retrieval in PIM, to improve both. This will be achieved by performing 3 studies that move from a conceptual understanding to proposing and evaluating concrete designs that improve retrieval: The Naturalistic Study will gather large-scale quantitative data on the effects of folder structure (e.g. depth and size) on retrieval success by videoing participants navigating to their files. The Tags Study examines the effect of tag vs. folder organizational structures on retrieval, comparing organization and retrieval behavior in both environments. The User-Subjective Study tests designs to improve retrieval by evaluating prototypes which implement the user-subjective approach developed by Dr. Bergman. One of its implementations was already successfully evaluated in the initial Marie Curie Fellowship. Dr. Bergman will lead in cooperation with Prof. Bar-Ilan (Head of Information Science at the host organization), Prof. Whittaker (Head of the initial Marie Curie Fellowship, who will also audit the project) and other EU researchers. These collaborative activities will lead to community building as Dr. Bergman will propose the first EU PIM workshop at INTERACT 2012."