The digital revolution has vastly increased the ability of the scientific community to collect and store a tremendous variety and quantity of data in digital form, representing a potentially irreplaceable legacy that can support scientific discovery and scholarship in both the present and the future. However, it is not yet clear what organizations or institutions can and should maintain and store such data, ensuring their long-term integrity and usability, nor how such long- term stewardship should be funded and supported. Many traditional information preservation and access institutions such as libraries and museums are struggling to develop the skills, resources, and infrastructure needed for large- scale, long-term digital data stewardship. Government agencies often have strong technical capabilities, but are subject to political and budgetary pressures and competing priorities. Private organizations and companies can bring to bear innovations not only in technology but also in economic approaches that could provide financial sustainability. Developing long-term collaborative partnerships between different types of organizations may be one approach to developing sustainable models for long-term data stewardship. The development of objective criteria and open standards for trusted digital data repositories is another important step towards sustainable data stewardship. A critical challenge is the development of viable economic models for ensuring that the resources needed for long-term stewardship are put in place, while at the same time addressing the needs of the scientific community and society more generally for open access to scientific data and information resources. The development of a robust spatial data infrastructure can not only help reduce both the short- and long-term costs of data stewardship, but also provide a framework for the establishment and evolution of trustworthy data repositories that will be available for future generations of users to discover, access, and use the scientific heritage that is being created today.