Environmental monitoring is the foundation for the scientific information necessary to make wise decisions key to meeting the twin goals of continued vigorous economic growth and preservation of our magnificent natural heritage for generations to come. Environmental monitoring must also be available to the public to inform them and facilitate their participation in our democracy. The knowledge we gain from improved monitoring of our rivers, forests, oceans and air is the knowledge we need to make informed decisions. This understanding is one of the pillars of our bridge to the twenty-first century. This report proposes a national framework for integrating environmental monitoring and related research on the Nation's ecological systems and resources. The framework links systematic observations and monitoring of ecological systems and resources with predictive modeling and process research. This linkage will provide the information needed to improve documentation of status and trends in the ecosystems and natural resources of the United States. Integration of our environmental monitoring and research networks will also provide the knowledge base required for selecting management approaches that ensure ecosystem and resource sustainability.