Student teaching has long been considered the most important component of an effective teacher education program. Recently, new research is finding links between these experiences and teacher candidates' future effectiveness, yet relatively little is known about the student teacher placement process and, in particular, the processes that lead to the matching of teacher candidates to the inservice teachers who supervise their student teaching ("cooperating teachers"). In this study, we examine the match process as well as the factors that influence these placement decisions. We also explore how, if at all, practices vary across teacher education programs (TEPs), districts, and schools. We find that, in broad terms, the process for matching student teachers to mentor teachers is similar across educational institutions, although TEPs and school systems sometimes face competing priorities when placing student teachers in classrooms. We also identify a problem of information asymmetry in the placement process, which leaves TEPs with questions about how cooperating teachers are selected and districts and schools with limited information with which to make thoughtful and intentional matches between candidates and cooperating teachers. Finally, we document the important role of social networks in placements and how they can advantage some TEPs, districts, and schools in this process.