The availability of requested network resources in a network of servers, each having associated network-servable resources of a specific kind is maintained. Resource data and resource-serving application software serve out the resource data and dynamically distribute capacity to serve out servable resources between the resource servers dependent on demand for the resources. The capability of the network as a whole to serve out a particular resource dependent upon the level of demand for the particular resource is thereby varied. The capacity to serve out servable resources is distributed between the resources without necessarily moving the resource data itself between the servers by distributing: resource-serving application software and/or installation software adapted to install resource-serving application software.