A system for automatic proximity-based preloading of relevant information in portable devices pre-loads a portable device such as a mobile telephone, a personal digital assistant (PDA) or portable computer before the occurrence of a trip or event, with information relevant to the user's current or upcoming tasks. The system locates and loads into the portable device only the information required by the user for near term projects, meetings, or trips. The system is generally comprised of an information catalog, a proximity estimator, a relevance estimator, an information retriever, and a device loader. The information catalog contains a list of the information sources and items to which the user has access and from which the system of the invention will retrieve data to be loaded into the mobile device. The proximity estimator determines the proximity of various relevant information items to the user's tasks based on distance, time, and/or association. The relevance estimator combines these proximity measures into a single relevance score. The most relevant information is retrieved by the information retriever and loaded onto the portable device by the device loader.