Children's learning--in the domains of science and religion specifically, but in many other cultural domains as well--relies extensively on testimony and other forms of culturally transmitted information. The cognitive processes that enable such learning must also administrate the evaluation, qualification, and storage of that information, while guarding against the dangers of false or misleading input. Currently, the development of these appraisal processes is not clearly understood. Recent work, reviewed here, has begun to address three important dimensions of the problem: how children and adults evaluate "truth" in communication, how they gauge the "inferential potential" of information, and how they encode and evaluate its "source."