A dynamic spectrum arbitrage method, comprising: establishing communication links between an e NodeB in a first communication network and a plurality of mobile devices; grouping the mobile devices into one of a plurality of tiers, each tier being associated with a priority; determining in a communications server (DPC, 5724) an amount of radio frequency, RF, spectrum resources available for allocation within the first communication network; allocating a portion of available RF spectrum resources of the first communication network for access and use by a second communication network; informing the second communication network that use of allocated RF spectrum resources may begin; and recording a transaction in a transaction database identifying an amount of RF spectrum resources allocated for use by the second communication network; monitoring, by the eNodeB, network resource usage of the first communication network; determining, by the eNodeB, whether usage of network resources exceeds a first threshold; restricting, by the eNodeB, originations of new sessions and handoffs of additional mobile devices from other base stations in response to determining that the usage of network resources exceeds the first threshold, wherein restricting originations of new sessions comprises restricting originations of new sessions for mobile devices grouped into a low priority tier; generating, by the eNodeB, a resource alert message based on monitoring of network resource usage and restricting originations and handoffs from other base stations; transmitting the resource alert message to the communications server (DPC, 5724); receiving in the communications server (DPC, 5724) the resource alert message that includes information collected by the eNodeB from the first communication network; determining in the communications server (DPC, 5724) whether at least some of the allocated RF spectrum resources are required by the first communication network based on the information included in the received resource alert message; informing the second communication network that use of allocated RF spectrum resources should be terminated in response to determining that at least some of the allocated RF spectrum resources are required by the first communication network; and updating the transaction database to include information identifying a time when use of the allocated RF spectrum resources was terminated by the second communication network. establishing communication links between an e NodeB in a first communication network and a plurality of mobile devices; grouping the mobile devices into one of a plurality of tiers, each tier being associated with a priority; determining in a communications server (DPC, 5724) an amount of radio frequency, RF, spectrum resources available for allocation within the first communication network; allocating a portion of available RF spectrum resources of the first communication network for access and use by a second communication network; informing the second communication network that use of allocated RF spectrum resources may begin; and recording a transaction in a transaction database identifying an amount of RF spectrum resources allocated for use by the second communication network; monitoring, by the eNodeB, network resource usage of the first communication network; determining, by the eNodeB, whether usage of network resources exceeds a first threshold; restricting, by the eNodeB, originations of new sessions and handoffs of additional mobile devices from other base stations in response to determining that the usage of network resources exceeds the first threshold, wherein restricting originations of new sessions comprises restricting originations of new sessions for mobile devices grouped into a low priority tier; generating, by the eNodeB, a resource alert message based on monitoring of network resource usage and restricting originations and handoffs from other base stations; transmitting the resource alert message to the communications server (DPC, 5724); receiving in the communications server (DPC, 5724) the resource alert message that includes information collected by the eNodeB from the first communication network; determining in the communications server (DPC, 5724) whether at least some of the allocated RF spectrum resources are required by the first communication network based on the information included in the received resource alert message; informing the second communication network that use of allocated RF spectrum resources should be terminated in response to determining that at least some of the allocated RF spectrum resources are required by the first communication network; and updating the transaction database to include information identifying a time when use of the allocated RF spectrum resources was terminated by the second communication network.