This chapter discusses challenges and possibilities involved in preserving biological diversity and the diversity of ecosystem services in the boreal zone and yet at the same time maintaining intensive timber extraction in boreal forests. Our focus is on Fennoscandian forests at the landscapes level, and we consider economic, social and ecological in the sustainability of forest management. We provide an outlook to boreal forest ecosystems and their history, and an overview of the forestry practices and policies that aim to ensure multi-functionality of Fennoscandian forests, i.e. diversity of efforts on sustaining biodiversity, timber production and other ecosystem services from forest landscapes. We review the current scientific understanding management effects on the structure and dynamics of the forest at different spatial, and the consequent repercussions on forest biodiversity and ecosystem services. Evidence suggests that many ecosystem services and biodiversity are in conflict with intensive timber production in boreal forests. We therefore present methods for assessing conflicts among alternative forest uses and for finding solutions for conflicts. We conclude the chapter by providing insights for future management aiming at sustainability from economic, ecological and social perspectives.