Many organizations now own hundreds of powerful workstations which are connected by local area networks. It is common practice in such organizations to allocate each of these workstations to a single user who exercises full control over the workstation’s resources. In such an environment we can find three types of users, casual users who seldom utilize the full capacity of their machines, sporadic users who for short periods of time fully utilize the capacity of the workstation they own, and frustrated users who for long periods of time have computing demands that are beyond the power of their workstations. Unlike the two other groups, the throughput of these frustrated users is limited by the power of their workstations. They often claim that their productivity could be significantly enhanced if they had access to the unutilized computing capacity of workstations owned by casual and sporadic users. Condor is a distributed batch system that was designed to meet the challenge posed by these users, namely to provide convenient access to unutilized workstations while preserving the rights of their owners. The current version of Condor was installed in our department for public use in the summer of 1988. It has since served more than 144,000 jobs that have consumed more than 6,000 days of CPU.