SRI's algorithm for address-block location (ABL) automatically finds the destination address on a mail piece and segments it into individual lines of text. The algorithm can distinguish the address from background patterns and lines preprinted on forms and labels, extraneous advertising, and speckle noise. SRI's ABL technology has been implemented as an all-software module in the USPS Recognition Coprocessor (RCP) for letter mail (Figure 1). This technology has also been implemented in a combination of digital hardware and software for processing images of flats mail, which are larger than letter mail (Figure 2). SRI's ABL algorithm has been deployed at USPS facilities since 1997. The deployed software also includes an ability to distinguish machine-printed addresses from hand-printed and script addresses, information that can be used to automatically select the appropriate OCR module for each individual mail piece.