evidence: Bollards, as functional street furniture, began with the Romans who constructed milestone markers, horse troughs, and tethering posts made of wood or stone. They later were used to protect pedestrians and buildings from horse-drawn vehicles. Bollards have long been used as short vertical posts for mooring boats and ships to docks. Our interest is in the variety of structures to control or direct road traffic. [...] Bollards should be used in areas where a clear delineation between vehicular traffic and pedestrians is desired such as at the mouth of major pedestrian walkways where they empty onto streets. Bollards restrict vehicular movements while providing for unimpeded pedestrian circulation. [...] Bollards play a key role in optimizing the use-potential of a site and limiting harm to operational and maintenance practices. They remind daily users of the overall integrity that a building and its environs portray. They warn potentially errant intruders that their intentions have been anticipated even during initial design planning. Bollards, standing in pairs or as long lines of sentinels are integral players in sustainable design.