On November 30 and December 1, 2010, nearly 60 representatives from federal agencies, nongovernmental organizations (NGOs), and scientific research institutions convened to discuss the observational data, monitoring networks, and indicators of climate change impacts on ecosystems in the United States. This group was convened to make progress toward two goals: 1) Outline a process for selecting indicators that represent the impacts of climate change on the nation's ecosystems. The intended use of this set of indicators is the ongoing assessment of impacts of climate change. These indicators would be incorporated in the National Climate Assessment (NCA), including in the next report, to be issued in 2013. 2) Identify opportunities for collaboration and coordination among existing and potential future observational networks that could be used to improve the understanding of the impacts of climate change on the nation's ecosystems.