Climate change is having impacts on the biodiversity and structure of many ecosystems. In this chapter, we focus on its impacts on forests. We will focus on how the potential climate change impacts on forest biodiversity and structure will have a reflection on the ecosystem services provided by forests, and therefore on the capacity of these ecosystems to support the Sustainable Development Goals set by the United Nations. The chapter will be organized in three sections, considering boreal, temperate and tropical forests along each section.The first section will deal with the synergies or interactions between climate change, biodiversity and ecosystem function with emphasis not only on plants but also on fungi, animals and prokaryotes. Synergies between climate change and ecosystem services will be described and analyzed in the second section. To better link the first two sections, we will explore the relationships between ecosystem function, species traits and ecosystem services. Finally, case