People today use the computer for many simultaneous work projects and activities. The traditional file system was developed for storing and retrieving files and it and the desktop have not evolved with users' practices. The first part of the dissertation presents a user study that generates a better understanding of the issues and practices regarding the organization of documents in support of activities. The second part provides the design of an environment to organize information based on an activity paradigm as opposed to an archiving paradigm and delivers the instantiation and the evaluation of a system based on such a design. The system, called Docksy, provides an environment structured in workspaces. Each workspace is segmented in areas or panels. Users can use documents as elements to structure their workflow or to manage their activities by separating files in the different panels, and by adding comments, tags, and flags. The Docksy design aims to create a flexible, lightweight environment that is easy to use and can be incorporated into users' daily practice, old or new. Such a system could be used to learn about users' practices and their evolution. Docksy was therefore developed for a double purpose; the short term purpose of testing new features (panels, comments, flags, and tags) and the long term purpose of facilitating learning about user practices. A study of Docksy use was conducted in which twenty participants used Docksy for at least two weeks and they were then interviewed. The study showed that participants valued the panels and the comment features. The results of the study showed the potential for changing users' practice and the potential for the system to be adopted by users.