Proactive approaches to sustainable development prevent the degradation of the Earth, respect the Earth's carrying capacity and assure sustainability of essential resources, processes, and products through the engineering, and reengineering, of production processes and of organizations. A proactive approach to sustainable development also includes interactive and reactive components. Tragedies and crises will occur, despite efforts to prevent them, and reactive techniques may often be the only way to diagnose and remedy such situations. To achieve these aims requires a broad understanding of many scientific disciplines and technologies, and their interactions leading to an integrated knowledge base for the sustainability of the world resources in their broadest sense.