The U.S. Department of Energy (DOE) has formed a nationwide network of seven regional partnerships to help determine the best approaches for capturing and permanently storing gases that can contribute to global climate change. The Regional Carbon Sequestration Partnerships (RCSPs) are tasked with determining the most suitable technologies, regulations, and infrastructure for carbon capture, transport, and storage in their areas of the country and parts of Canada. The seven partnerships include more than 350 state agencies, universities, national laboratories, private companies, and environmental organizations, spanning 42 states, two Indian nations, and four Canadian provinces. The Regional Partnerships initiative is being implemented in three phases: •Characterization Phase (2003-2005): The objective was to collect data on CO
2 sources and sinks and develop the human capital to support and enable future carbon sequestration field tests and deployments. The completion of this Phase was marked by release of the Carbon Sequestration Atlas of the United States and Canada-Version 1 which included a common methodology for capacity assessment and reported over 3,000GT of storage capacity in saline formations, depleted oil and gas fields, and coal seams.•Validation Phase (2005-2009): The objective is to plan and implement small-scale (<1 million tons CO
2) field testing of storage technologies in areas determined to be favorable for carbon storage. The partnerships are currently conducting over 20 small-scale geologic field tests and 11 terrestrial field tests.•Development Phase (2008-2018): The primary objective is the development of large-scale (>1 million tons of CO
2) Carbon Capture and Storage (CCS) projects, which will demonstrate that large volumes of CO
2 can be injected safely, permanently, and economically into geologic formations representative of large storage capacity. Even though the RCSP Program is being implemented in three phases, it should be viewed as an integrated whole, with many of the goals and objectives transitioning from one phase to the next. Accomplishments and results from the Characterization Phase have helped to refine goals and activities in the Validation and Deployment Phases. The RCSP Program encourages and requires open information sharing among its members by sponsoring both general workshops and meetings to facilitate information exchange. Although each RCSP has its own objectives and field tests, mutual cooperation has been an important part of the Program thus far. The primary goal of the RCSP initiative is to promote the development of a regional framework and the infrastructure necessary to validate and deploy carbon sequestration technologies within each Partnership's region.