The current study examines the personal epistemology of fourth-grade elementary school teachers from Germany (n = 10) and the United States (n = 10) to gain a more nuanced understanding of teachers' beliefs about knowledge and knowing through a cross-cultural lens. Analyses of semi-structured interviews reveal similarities and differences in the statements of teachers. Four themes are identified: The majority of teachers believed that (a) knowing is uncertain and (b) knowledge has domain-specific qualities; (c) U.S. teachers seemed to view knowledge more as being embedded within their community, while (d) German teachers discussed more internal knowledge sources. The general discussion includes possible cross-cultural explanations for these four emerging themes and points tentatively to developmental issues stemming from uncertainty beliefs. Conceptual and educational implications are discussed and suggestions for future research are given. (Contains 2 tables and 1 figure.)