1. In a client/server system in which incoming work requests are queued for processing by one or more worker threads of one or more server processes and in which units of work are organized into enclaves with the units of work in each enclave being managed as a single entity by a workload manager, each of said enclaves having a workload manager classification for determining a share of system resources to be given to units of work in that enclave, a method of controlling the assignment of said worker threads to said enclaves, comprising the steps of: in response to the receipt of an incoming work request, defining an enclave for said work, request and adding said work request to a queue of incoming work requests to enqueue said request; and in response to a request from a worker thread for more work, removing a work request from said queue to dequeue said request and associating slid worker thread with the enclave defined for said request; and providing said worker thread while processing said request from said queue with a share of system resources based on the workload manager classification of said enclave.