This tutorial explains the relationship between Topic Maps and concepts that are of central importance to librarians and library scientists. It assumes familiarity with the basic concepts of Topic Maps equivalent to that gained by attending the tutorial Understanding Topic Maps. Among the topics explored are metadata (including MARC and Dublin Core), thesauri and subject classification systems (such as LCSH and SKOS), Functional Requirements for Bibliographic Records (FRBR), and the role of Topic Maps in digital libraries. Someone once posed the rhetorical question whether librarians can save the world (from infoglut). The answer suggested by this tutorial is yes – provided they learn how to apply the power of Topic Maps!