A wide variety of wildlife species occur in red spruce (Picea rubensRed spruce ()) and spruce-fir forests, and these forest types represent optimal habitatHabitat for several vertebrate and invertebrateInvertebrate species of conservation concern. In this chapter, we synthesized our understanding of wildlife diversityDiversity in red spruceRed spruce () and spruce-fir ecosystems in the central and southern Appalachians, and identified species that are reliant on occurrence of these ecosystems. We also reviewed six major insect pests of red spruceRed spruce () in our focal regions. Red spruceRed spruce () and spruce-fir ecosystems are important habitatsHabitat for at least 1 fishFish, 7 amphibianAmphibian, 14 avian, and 3 mammalMammal species, with well over 100 additional vertebrate species known to occur in these forest types. Three federally listed species are strongly associated with red spruceRed spruce () or spruce-fir forests, including the Cheat Mountain salamander (Plethodon nettingiCheat Mountain salamander ()), Carolina northern flying squirrel (Glaucomys sabrinus coloratusCarolina northern flying squirrel ()), and spruce-fir moss spider (Microhexura montivagaSpruce-fir moss spider). Our knowledge synthesis provides managers and biologists with a single reference to assist with identifying local wildlife species that would most benefit from restoration and management of red spruceRed spruce () and spruce-fir ecosystems.