A method to assess a state of a portable item as being extant (503.1) or being displaced (503.0); the method performed by a hardware processor configured for use when the hardware processor is at least one of collocated with and attached to, or embedded within, the portable item; the processor coupled with a non-volatile memory (206.M.N) and with one or more environmental sensors which are also collocated with and attached to or embedded within the portable item including at least a motion sensor (210.M) and at least one of a location sensor (210.L) and a clock; the method comprising: storing in the non-volatile memory (206.M.N.) an item usage expectation comprising: a detection context for monitoring the portable item, the detection context comprising at least one of a specified date (105, 144.T), a specified time interval (105, 144.T), and a specified location (104.L) for use or storage of the portable item, and an associated expected personal motion (144.M) for the portable item, wherein the motion of the item is to be assessed locally at the item via the motion sensor (210.M), said motion sensor (210.M) configured to detect locally at the portable item at least one of: a personal motion indicative of local movement of the portable item by a person who possesses said item and a lack of any motion of said portable item wherein the item is stationary; receiving from the at least one of the location sensor (210.L) and the clock data indicative that the portable item is within the detection context of the usage expectation; comparing locally via the hardware processor: a current motion (104.M) of the portable item detected via the motion sensor (210.M) with the expected personal motion (144.M) for the portable item defined in the usage expectation; and assessing locally by the hardware processor, based on the comparison, whether within the detection context the portable item has a motion which conforms to the expected personal motion (144.m); making a determination via the hardware processor, based on the assessment, as to whether the portable item is extant (503.1) or displaced (503.0); and in response to an assessment that the portable item is displaced, signalling, via the hardware processor, an alert (372, 374) that the portable item is displaced (503.0). storing in the non-volatile memory (206.M.N.) an item usage expectation comprising: a detection context for monitoring the portable item, the detection context comprising at least one of a specified date (105, 144.T), a specified time interval (105, 144.T), and a specified location (104.L) for use or storage of the portable item, and an associated expected personal motion (144.M) for the portable item, wherein the motion of the item is to be assessed locally at the item via the motion sensor (210.M), said motion sensor (210.M) configured to detect locally at the portable item at least one of: a personal motion indicative of local movement of the portable item by a person who possesses said item and a lack of any motion of said portable item wherein the item is stationary; a detection context for monitoring the portable item, the detection context comprising at least one of a specified date (105, 144.T), a specified time interval (105, 144.T), and a specified location (104.L) for use or storage of the portable item, and an associated expected personal motion (144.M) for the portable item, wherein the motion of the item is to be assessed locally at the item via the motion sensor (210.M), said motion sensor (210.M) configured to detect locally at the portable item at least one of: a personal motion indicative of local movement of the portable item by a person who possesses said item and a lack of any motion of said portable item wherein the item is stationary; receiving from the at least one of the location sensor (210.L) and the clock data indicative that the portable item is within the detection context of the usage expectation; comparing locally via the hardware processor: a current motion (104.M) of the portable item detected via the motion sensor (210.M) with the expected personal motion (144.M) for the portable item defined in the usage expectation; and a current motion (104.M) of the portable item detected via the motion sensor (210.M) with the expected personal motion (144.M) for the portable item defined in the usage expectation; and assessing locally by the hardware processor, based on the comparison, whether within the detection context the portable item has a motion which conforms to the expected personal motion (144.m); making a determination via the hardware processor, based on the assessment, as to whether the portable item is extant (503.1) or displaced (503.0); and in response to an assessment that the portable item is displaced, signalling, via the hardware processor, an alert (372, 374) that the portable item is displaced (503.0).