A security checkpoint screening system comprising: a) a checkpoint screening station (12, 14, 16, 100, 1200) having: i) a scanning area including a scanning device (18, 1214) for scanning items with penetrating radiation to derive image data, the image data conveying images of the items; ii) a pre-scan area lying before the scanning area; iii) at least two post-scan areas (1206 1208), the at least two post scan areas including an item collection area and an area for dispatch to secondary screening; iv) a switching area to direct the items to different post-scan areas of the at least two post-scan areas; v) a conveyor system including mechanical switches in the switching area of the checkpoint screening station for controlling a displacement of the items through the security checkpoint screening system, wherein the conveyor system includes respective conveyor sections in the item collection area and in the area for dispatch to secondary screening; b) a processing module programmed with software for: i) receiving the image data derived by scanning the items with the scanning device (18, 1214); ii) assigning threat level indicators to items associated with the images conveyed by the image data at least in part based on threat assessment information provided by a human operator at a remote screening station located remotely from the checkpoint screening station; and c) a control device programmed for electronically controlling a displacement of the items through the security checkpoint screening system by using the assigned threat level indicators to control the mechanical switch of the conveyor system in the switching area of the checkpoint screening station so that corresponding items are directed to a proper one of the at least two post-scan areas, characterized by the checkpoint screening station further comprising: vi) a divider wall to isolate a portion of the conveyor system to prevent passengers from accessing items being displaced by the conveyor system until the items have been marked as clear and have reached the item collection area. a) a checkpoint screening station (12, 14, 16, 100, 1200) having: i) a scanning area including a scanning device (18, 1214) for scanning items with penetrating radiation to derive image data, the image data conveying images of the items; ii) a pre-scan area lying before the scanning area; iii) at least two post-scan areas (1206 1208), the at least two post scan areas including an item collection area and an area for dispatch to secondary screening; iv) a switching area to direct the items to different post-scan areas of the at least two post-scan areas; v) a conveyor system including mechanical switches in the switching area of the checkpoint screening station for controlling a displacement of the items through the security checkpoint screening system, wherein the conveyor system includes respective conveyor sections in the item collection area and in the area for dispatch to secondary screening; i) a scanning area including a scanning device (18, 1214) for scanning items with penetrating radiation to derive image data, the image data conveying images of the items; ii) a pre-scan area lying before the scanning area; iii) at least two post-scan areas (1206 1208), the at least two post scan areas including an item collection area and an area for dispatch to secondary screening; iv) a switching area to direct the items to different post-scan areas of the at least two post-scan areas; v) a conveyor system including mechanical switches in the switching area of the checkpoint screening station for controlling a displacement of the items through the security checkpoint screening system, wherein the conveyor system includes respective conveyor sections in the item collection area and in the area for dispatch to secondary screening; b) a processing module programmed with software for: i) receiving the image data derived by scanning the items with the scanning device (18, 1214); ii) assigning threat level indicators to items associated with the images conveyed by the image data at least in part based on threat assessment information provided by a human operator at a remote screening station located remotely from the checkpoint screening station; and i) receiving the image data derived by scanning the items with the scanning device (18, 1214); ii) assigning threat level indicators to items associated with the images conveyed by the image data at least in part based on threat assessment information provided by a human operator at a remote screening station located remotely from the checkpoint screening station; and c) a control device programmed for electronically controlling a displacement of the items through the security checkpoint screening system by using the assigned threat level indicators to control the mechanical switch of the conveyor system in the switching area of the checkpoint screening station so that corresponding items are directed to a proper one of the at least two post-scan areas, characterized by the checkpoint screening station further comprising: vi) a divider wall to isolate a portion of the conveyor system to prevent passengers from accessing items being displaced by the conveyor system until the items have been marked as clear and have reached the item collection area.