Resources associated with a communication system switch are monitored by storing information defining one or more resource groups. Each of the resource groups includes multiple identifiers, with each of the identifiers specifying at least one resource to be monitored. A client external to the switch is permitted to select at least one of the resource groups for monitoring. In response to selection of one of the groups by the client, monitoring of the corresponding resources is established on behalf of the client. The resource monitoring may be established, controlled and maintained by a telephony server coupled between the client and the switch. Such a telephony server can preserve monitoring for a resource group, independent of the requests of clients, in order to reduce the amount of execution time needed to set up and tear down monitors for client applications. This is particularly advantageous in call centers or in other client applications that involve monitoring large numbers of switch resources.