The project fragmentation problem in personal information management occurs when someone who is working on a single project stores and retrieves information items relating to that project from separate format-related collections (documents, emails and favorite Web sites). This study was aimed to test empirically users' working habits in order to shed light on the project fragmentation problem. Twenty personal computer users participated in the study. Data collection tools included an interview, screen captures and a questionnaire. Results indicate that users tend to store and retrieve project-related information items based on different formats in one project folder when the interface design encourages it. However, they store and retrieve project-related information items in different folders (documents, emails and favorite Web sites) when the design encourages such fragmentation. Two types of attempts to solve the project fragmentation problem are reviewed and a new possible solution is suggested.