A personnel authentication and tracking system comprising: a personnel authentication control system; one or more personnel authentication and tracking appliances in known fixed locations in a building and covering corresponding detection regions in the building; and personnel authentication and tracking tags; wherein the personnel authentication and tracking appliance comprises a processor and memory configured to: authenticate tracking tags passing through detection regions against an access control list; receive data that identifies a number of people passing through or within the detection regions and is based on images received from cameras; compare the number of people identified by the received data with the number of tracking tags identified by the system; and cause an alarm to be asserted when the number of people identified in a particular detection region exceeds the number of tracking tags in the particular detection region; and wherein the personnel authentication control system comprises a processor configured to, during an emergency situation: collect data from the personnel authentication and tracking appliances; produce paths of tracking tags, as the tracking tags pass through the detection regions associated with the personnel authentication and tracking appliances, based on the known fixed locations of the personnel authentication and tracking appliances in the building; and render, on a rendering device, a map of a schematic of the building depicting the various paths taken by the tracking tags. a personnel authentication control system; one or more personnel authentication and tracking appliances in known fixed locations in a building and covering corresponding detection regions in the building; and personnel authentication and tracking tags; wherein the personnel authentication and tracking appliance comprises a processor and memory configured to: authenticate tracking tags passing through detection regions against an access control list; receive data that identifies a number of people passing through or within the detection regions and is based on images received from cameras; compare the number of people identified by the received data with the number of tracking tags identified by the system; and cause an alarm to be asserted when the number of people identified in a particular detection region exceeds the number of tracking tags in the particular detection region; and wherein the personnel authentication control system comprises a processor configured to, during an emergency situation: collect data from the personnel authentication and tracking appliances; produce paths of tracking tags, as the tracking tags pass through the detection regions associated with the personnel authentication and tracking appliances, based on the known fixed locations of the personnel authentication and tracking appliances in the building; and render, on a rendering device, a map of a schematic of the building depicting the various paths taken by the tracking tags. authenticate tracking tags passing through detection regions against an access control list; receive data that identifies a number of people passing through or within the detection regions and is based on images received from cameras; compare the number of people identified by the received data with the number of tracking tags identified by the system; and cause an alarm to be asserted when the number of people identified in a particular detection region exceeds the number of tracking tags in the particular detection region; and wherein the personnel authentication control system comprises a processor configured to, during an emergency situation: collect data from the personnel authentication and tracking appliances; produce paths of tracking tags, as the tracking tags pass through the detection regions associated with the personnel authentication and tracking appliances, based on the known fixed locations of the personnel authentication and tracking appliances in the building; and render, on a rendering device, a map of a schematic of the building depicting the various paths taken by the tracking tags. collect data from the personnel authentication and tracking appliances; produce paths of tracking tags, as the tracking tags pass through the detection regions associated with the personnel authentication and tracking appliances, based on the known fixed locations of the personnel authentication and tracking appliances in the building; and render, on a rendering device, a map of a schematic of the building depicting the various paths taken by the tracking tags.