Abstract: A mobile electronic control device, such as an electronic key, is used to access or otherwise control the operations of a field device, such as an appliance, power tool, shipping container, etc. In a control event in which the mobile control device interacts with the field device via wired or wireless communications, the control device obtains the current location and the field device ID. The communications between the mobile control device and the field device may be secured with encryption. The location information is used by the mobile control device to determine whether the field device should be accessed or enabled. Alternatively, the location information may be stored separately in a location sensing device, and the control event data recorded by the key and the location information recorded by the location sensing device are later combined when they are downloaded into a management system for auditing.