Abstract: Working assets (26) are equipped with ID tags (56) that respond to interrogations from interrogators (50). Each interrogated tag (56) sends response codes that identify the tag (56) and working asset (26), can describe an amount of use experienced by the working asset (26), and can describe unused capacity available for holding a consumable commodity, such as fuel. Interrogators (50) are positioned at normally closed portals (40, 42, 62, 64) of staging areas (22, 24). A database (94) contains information concerning working assets (26), users (28) to whom working assets (26) have been assigned, and caretakers (38) who may be authorized to transport various working assets (26). The caretakers (38) also have ID tags (58). A portal (40, 42, 62, 64) temporarily opens or remains closed in response to the interrogation that takes place at the portal (40, 42, 62, 64) and data stored in the database (94).