INCREASED PUBLIC ACCESS TO NATIONAL PARKS is an important artifact of the last century’s technological development. The expansion of aircraft flight-seeing, snowmobile use, and motorcycle touring are examples of technologic advancements that now commonly impact national park soundscapes (see Barber et al., [article 1, article 2, article 3], and Park et al., this volume). To adequately manage these impacts, the National Park Service (NPS) must see them as part of an evolution toward a noisier society rather than as isolated, situation-specific events. The natural soundscape also needs to be perceived across society as an elemental and foundational feature of a protected area. This special issue of Park Science illustrates some of the ways the National Park Service is building capacity to maintain the resilience of the natural soundscape (Walker and Salt 2006) in this context. Planning, management, and research are all under way to better understand the roles and functions of natural sound in the ecologic and human values of protected areas. But key questions remain: How do changes in the natural soundscape alter the other components of a protected area to which the soundscape is fundamental? At what point will the broader system change to an entirely different state from which it may never return?

The National Park Service must see [intrusions on natural soundscapes] as part of an evolution toward a noisier society rather than as isolated, situation-specific events.