Ecosystems provide important services that can help people adapt to climate variability and change. Scientific literature provides evidence that EBA with forests and trees can reduce social vulnerability to climate hazards; however, uncertainties and knowledge gaps remain. Pilot projects under implementation also provide information on EBA and can serve as learning sites. Based on different sources of information from scientific literature and experiences on the ground, we discuss the potential of forests and trees for EBA in several cases: forests and trees providing goods to local communities facing climatic threats; trees in agricultural fields regulating water, soil, and microclimate for more resilient production; forested watersheds regulating water and protecting soils for reduced climate impacts; forests protecting coastal areas from climate-related threats; and forests regulating rainfall at the regional or continental level. We discuss uncertainties, knowledge gaps and controversies regarding EBA. We show that uncertainties are important for adaptation based on the regulating services of forests and trees for protecting watersheds and coastal areas and regulating regional rainfall. The multiple benefits of EBA for biodiversity conservation and climate change are also well recognized but trade-offs exist between ecosystem services or between their beneficiaries. Better understanding is needed of the efficiency, costs, and benefits, and trade-offs of EBA with forests and trees.