In this paper we provide an overview of Federal sources of social indicator data on children’s well-being that provide estimates at the state-level, that is, for children in individual states. Twenty-one major survey and administrative data sources are summarized and discussed. (See Table 2.) Areas of strength are identified, as are important gaps and opportunities for future development. In addition, we provide an Appendix that includes systematic one- to two-page summaries for each of the data sources reviewed for purpose, content, and periodicity.