lecting priorities and approaches to peer reviewing scientific results, and to give a restructured climate change science program the authority to communicate results to the public in a timely fashion.

Climate change is critically important to our nation and the world. Addressing the challenges posed by climate change will require a strengthened research program aimed at understanding climate variability and change as well as supporting robust approaches for mitigating the causes and anticipating and adapting to the expected changes. Although this end-to-end approach was called for in the CCSP strategic plan (CCSP, 2003), for it to be realized, the emphasis will have to be shifted toward understanding the complex interactions between climate, humans, and the environment. This, in turn, will require a more integrated approach to research—one without the false dichotomies between natural and social science, between scientific disciplines, and between basic and applied science. To ensure that this shift also succeeds in producing information that decision makers need, stronger connections will have to be forged with major groups of stakeholders (e.g., water resource and land managers, policy makers), who can contribute data to support research objectives, guide the development of a national assessment and a national climate service, and benefit from the results. Fortunately, the successes of the CCSP and its predecessor USGCRP provide a strong foundation for making this transition to meet today’s challenges.