This article reports on findings of an online survey about academic instruction librarians' conceptions and experiences of teacher agency in relation to their instructional work, and, more specifically, on the role of librarian-faculty relationships in these conceptions and experiences. The research study is informed by an ecological model of teacher agency, according to which agency is understood in terms of not only individual choices and actions, but also relationships and interactions among individuals and groups and the environmental conditions in which they interact. This article builds on the findings reported in a previously published article that concentrated on study participants' conceptions of teacher agency and their affective orientations toward the concept.