The Library of Congress is sponsoring a set of legislative data challenges to advance the development of international data exchange standards for legislative data. These challenges are an initiative to encourage broad participation in the development and application of legislative data standards and to engage new communities in the use of legislative data. Goals of this initiative include: • Enabling wider accessibility and more efficient exchange of the legislative data of the United States Congress, • Encouraging the development of open standards that facilitate better integration, analysis, and interpretation of legislative data, • Fostering the use of open source licensing for implementing legislative data standard.