Defines the key terms for use in the specification of biometric technologies in a VSS, including metrics for defining performance; provides guidance on selection of camera types, placement of cameras, image specification etc. for the operation of a biometric recognition capability in conjunction with a VSS; provides guidance on the composition of the gallery (or watchlist) against which facial images from the VSS are compared, including the selection of appropriate images of sufficient quality, and the size of the gallery in relation to performance requirements; makes recommendations on data formats for facial images and other relevant information (including metadata) obtained from video footage, used in watchlist images, or from observations made by human operators.