This chapter starts off from standard takes on knowledge organization and classification in libraries and encyclopedias, but then zeros in on the field of information retrieval, which develops in fundamental opposition to even the most visionary of library techniques. Coordinate indexing, the first technique in this lineage, is explicitly designed to eliminate the influence of librarians and other knowledge mediators by shifting expressive power from the classification system to the query and, by extension, to the information seeker. Order is no longer understood as a stable map to the universe of knowledge but increasingly as the outcome of a dynamic and purpose-driven process of ordering. The chapter closes by discussing coordinate indexing as a precursor of the relational model for database management.