When an application that executes under PRM is invoked, a job manager is automatically started on the workstation. Figure 1 shows the flow of control: the job manager determines the resource requirements of the job and sends resource requests to one or more system managers (1); if the requested resources are available the system manager informs the node manager responsible for each resource that the resource has been assigned to particular job manager (2); the system manager returns a list of the assigned resources to the job manager (3); the job manager allocates assigned resources to the job's tasks and contacts the node manager to invoke the application (4); upon receipt of a request from the authorized job manager, each node manager loads the application task (5).