Teachers engaged in sustained collaboration with a teacher librarian were interviewed about the meaning of that collaboration. The findings suggest that the teachers recognized important contributions of the librarian to instructional planning and classroom instruction including knowledge, legwork, and support. In particular, they understood her role as a broker both to resources and to ideas for using those resources in instruction. While these resources were essential, they were not sufficient; they required a knowledgeable peer who also understood their application to the curriculum and what students were expected to learn. They required a librarian