Next-generation projects in High Energy Physics will reach again a new dimension of complexity. Information management has to ensure an efficient and economic information flow within the collaborations, offering world-wide up-to-date information access to the collaborators as one condition for successful projects. DESY introduces several information systems in preparation for the planned linear collider TESLA: a Requirements Management System (RMS) is in production for the TESLA planning group, a Product Data Management System (PDMS) is in production since the beginning of 2002 and is supporting the cavity preparation and the general engineering of accelerator components. A pilot Asset Management System (AMS) is in production for supporting the management and maintenance of the technical infrastructure, and a Facility Management System (FMS) with a Geographic Information System (GIS) is currently being introduced to support civil engineering. Efforts have been started to integrate the systems with the goal that users can retrieve information through a single point of access. The paper gives an introduction to information management and the activities at DESY.