The research of the last decade has demonstrated that ecosystems and human systems are influenced by multiple factors, including climate, land use, and the by-products of resource use. Understanding the net impact of a suite of simultaneously occurring environmental changes is essential for developing effective response strategies. Using case studies on drought and a wide range of atmosphere-ecosystem interactions, a workshop was held in September 2005 to gather different perspectives on multiple stress scenarios. The overarching lesson of the workshop is that society will require new and improved strategies for coping with multiple stresses and their impacts on natural socioeconomic systems. Improved communication among stakeholders; increased observations (especially at regional scales); improved model and information systems; and increased infrastructure to provide better environmental monitoring, vulnerability assessment, and response analysis are all important parts of moving toward better understanding of and response to situations involving multiple stresses. During the workshop, seven near-term opportunities for research and infrastructure that could help advance understanding of multiple stresses were also identified. Table of ContentsFront MatterSummary1 Introduction2 Drought3 Atmosphere-Ecosystem Interactions4 Lessons Learned from the Case StudiesReferencesAppendix A Statement of TaskAppendix B Workshop AgendaAppendix C Workshop ParticipantsAppendix D Extended Speaker AbstractsAppendix E Committee Biosketches