Critiques of hegemonic library classification structures and controlled vocabularies have a rich history in information studies. This project has pointed out the trouble with classification and cataloging decisions that are framed as objective and neutral but are always ideological and worked to correct bias in library structures. Viewing knowledge organization systems from a queer perspective, however, challenges the idea that classification and subject language can ever be finally corrected. Engaging queer theory and library classification and cataloging together requires new ways of thinking about how to be ethically and politically engaged on behalf of marginal knowledge formations and identities who quite reasonably expect to be able to locate themselves in the library. Queer theory invites a shift in responsibility from catalogers, positioned to offer functional solutions, to public services librarians, who can teach patrons to dialogically engage the catalog as a complex and biased text, just as critical catalogers do.