The present invention relates to a distributed computing system and method. Conventional distributed computing environments require complex arrangements to distribute tasks and to collate the results of any distributed processing. There has been a recent trend towards using the spare computing capacity of computers connected to the Internet to provide distributed computing resources. However, various security issues have been identified in relation to such an arrangement. Suitably, the present invention uses a power management system in which a user or system context, which is created and saved when an associated computing system enters a power management state, to provide a distributed computing platform. Once a computer system has entered a power saving state and the user system context has been saved to an HDD, the computer system is arranged to wake-up and to establish, or use, a pre-prepared distributed computing task system context. The power management system is instructed to load and restore the distributed computing task system context, rather than the conventional user system context. In this manner a distributed computing platform using the computer systems that are connected to an Intranet can be used for performing distributed computing. Since the user system context and the distributed computing task system context are not resident within the computer system concurrently, the security issues are at least partially alleviated.