Book excerpt: Agroforestry in Sustainable Agricultural Systems examines the environmental and social conditions that affect the roles and performance of trees in field- and forest-based agricultural production systems. Various types of ecological settings for agroforestry are analyzed within temperate and tropical regions. The roles of soil, water, light, nutrient and pest management in mixed, annual, woody perennial and livestock systems are discussed. Important new case studies from around the world offer innovative strategies that have been used successfully in raising forests and tree products on a sustainable basis for commercial harvesting and for providing other environmental services in land conservation and watershed management.