Preface. EcoSummit Participant List. Introduction: Understanding and Solving Environmental Problemsin the 21st Century: Toward a new, integrated "hard problem science" (R. Costanza, S.E. Jørgensen). References. 1. Integrated Assessment and Modeling - Science for Sustainability (G. Harris). Abstract. Introduction. The global context. Changes to the enterprise of scientific research. "Clean and green" drivers on policy and markets. The science of IA and IAM - integration and synthesis. IAM and ESM - the science of the future? References. 2. The Potential for Integrated Assessment and Modeling to Solve Environmental Problems: Vision, Capacity, and Direction (P. Parker et al.). Introduction. Integration. Visions of the future. Optimistic view. Pessimistic view. Evolution of IAM. IAM current position: Points of agreement. Case studies. Model complexity. Validation. Integrated Assessment. Agent-based models. Communication. Values in models. Future of IAM. Links to other groups. Conclusion. References. 3. Complex Adaptive Hierarchical Systems (B.C. Patten et al.). The new confrontation - biocomplex wholeness. Complexity. Adaptation and hierarchy. Measuring the organizational complexity of CAHSystems. Measuring the complexity of genomes and organisms - biocomplexity. Exergy-based orientors in a natural (virgin) forest. Exergy and information of solar radiation. Emergy and exergy. Integration of orientors. Adaptation and hierarchy, again. Systemicity. Eco-anthropic CAHSystems. A polycentric approach to integrated assessment. Eco-geological assessment towards sustainable coastal development inYogyakarta, Indonesia - scale adjustment to observe and analyze CAHSystems. Contents. Concluding thoughts. Glossary. References. 4. Complex Adaptive Hierarchical Systems (B.C. Patten et al.). Introduction. About theory. About applications. About modeling. Conclusions. References. 5. Ecosystem Services, Their Use and the Role of Ecological Engineering:State of the Art (A. Dakers). Introduction. Defining ecosystem services. Humankind's relationship with the natural environment. Anthropocentric or ecocentric valuing. Ecosystem relationships - embeddedness. Valuing ecosystem services. The use and misuse of ecosystem services. Designing and engineering to restore a sustainable relationship with ecosystems. Making better use of ecosystem services. Frontline projects. Players involved in achieving better use of ecosystem services. Engineer as designer. Ecological engineering. Case Study 1: Ministry of Transport in the Netherlands. Case Study 2: Oxelösund Våtmark, Sweden. Case Study 3: Donaumoos - Germany. Case Study 4: Kaja, Ås, Norway. Case Study 5: Aremark. Case Study 6: Kågeröd Recycling Project. Case Study 7: Ruswil, Switzerland. Case Study 8: Calcutta Wastewater-fed Aquaculture. Case Study 9: Stensund Aquaculture Centre. Case Study 10: Water Enhancement Programme, Christchurch. Case study evaluation. Under-utilization of ecosystem services. Conclusions. Acknowledgements. References. 6. Ecosystem Services (B. Guterstam et al.). Introduction. Ecosystem services. Key questions and common ground. The role of ecosystems services tomorrow. Conclusions. References. 7. Science and Decision-Making (V.H. Dale). Science and decision-making. Scientists' role in decision-making. Three case studies. Mount St. Helens. Tennessee Cedar Barrens. The Brazilian Amazon. Lessons learned. Characteristics of scientists and decision-makers influence how they interact. Questions about the relationship between science and decision-making. Acknowledgements. References. 8. Science and Decision-Making (E.J. Rykiel Jr. et al.). Introduction. Working definitions. Multiple roles of science. The role of scientists in controversial issues. Scientists and activism. Education of scientists. Science based on holism. Increasing the effectiveness of the individual environmental scientist. Pathways to involvement in decision-making. Changing the environmental science curriculum.