Forest biodiversity is fundamental to ecosystem functioning, facilitating processes such as nutrient cycling, pollination and seed dispersal. A healthy forest provides a range of economic, societal and cultural values and services beyond timber production, including recreation, carbon sequestration, ecotourism, landscape aesthetics and the intrinsic value of biodiversity to society. Despite this, forest biodiversity remains under increasing pressure from agricultural conversion and intensive, large-scale, yield-driven forest management approaches. In this chapter, the authors explore how these approaches alter forest biodiversity and, in particular, species of conservation concern. The authors outline how sustainable forest management can be used to maintain or enhance biodiversity. Two case studies are provided that illustrate these concepts in contrasting biomes: managing forest biodiversity in landscapes of low forest cover, a case study from temperate plantation forestry in Ireland; and, managing forest biodiversity by emulating natural ecosystem dynamics, a case study from boreal mixedwood forests in Canada.