This report summarizes information on the status of the Great Lakes basin ecosystem drawn from the State of the Great Lakes 2005 report. Indicator reports presented at the State of the Lakes Ecosystem Conference (SOLEC) held in Toronto, Ontario, in October 2004, are used to form the basis of both the Highlights and the State of the Great Lakes 2005 reports. Fifty-six indicators under the following nine categories were assessed: Human Health, Land Use-Land Cover, Contamination, Biotic Communities, Invasive Species, Aquatic Habitats, Coastal Zones, Resource Utilization and Climate Change. In addition, each lake basin, the St. Clair River-Lake St. Clair-Detroit River ecosystem and the St. Lawrence River were also assessed using available information.