DataONE itself does not store data.
DataONE connects multiple data repositories in a federated network to provide integrated search and discovery and to provide replication services to the data repositories within the federation. Data are stored, and made visible, by the individual data repositories (see 'Contribute Data'). In DataONE language, these repositories are termed 'Member Nodes' (not all Member Nodes within DataONE are repositories but all repositories collaborating with DataONE are Member Nodes). At launch, DataONE comprised eight Member Nodes and more are being added (see 'Current Member Nodes' for a full list and link to operation documents).
DataONE is also collaborating with the White House Office of Public Engagement, the Office of Science and Technology Policy and the U.S. Department of Transportation on their safety data challenge. More information about this project and associated data can be found here.