Souvenir cards by private bank note companies represent some of the earliest cards in the SCCS catalog, dating back as far as 1836. Many of these were printed by predecessors of the American Bank Note Company or by firms that would later merge with it. All these companies were capable of producing high-quality intaglio engraved work. Most of these cards were souvenir invitations, programs, and menus for special events such as banquets, inaugural balls, or anniversary commemorations. Though "forerunner" does not suitably describe modern cards, as the FSO category extends into the 1980s, this category includes souvenir cards that are not part of the regular Semi-Official listings. Since unknown FSO cards occasionally surface, a year-based numbering system allows for easy inclusion of new discoveries. The SCCS is grateful to Art Benjamin, Paul Melnick, and Bill Kriebel, whose collections contain many of the rare cards shown here.