An apparatus includes a carrier, and a system that is responsive to wireless signals transmitted by tags on items carried by the carrier for maintaining a local inventory of items carried by the carrier. A different apparatus involves a carrier having a container with an interior, a sensor for detecting a condition externally of the container that can be related to an environment within the container, and a system that handles information from the sensor in a manner facilitating an evaluation of the likelihood that a problem exists within the container. Another apparatus involves a carrier for a plurality of items, and a system that is responsive to wireless signals received from a remote location for determining a current location of the carrier and for evaluating whether the carrier is proceeding along an intended route.