To provide a self-checkout system and method and/or device applicable to an arbitrary store.

The self-checkout system provided with a plurality of self- checkout stations for self-assisted purchasing each including self-checkout terminal equipment, a bagging area and an article moving area, is provided with at least one monitoring terminal device for monitoring the purchasing operation of at least any one of the plurality of self-checkout stations. The self-checkout system is applicable to use based on various kinds of configurations, purposes and capacities. In a certain configuration, two or more monitoring terminal devices are installed and each of the devices is operated for monitoring one or more stations among the plurality of self-checkout stations.