The purpose of this study is to examine how the diverse members of the mathematics education community (in-service secondary mathematics teachers, in-service secondary mathematics teachers, university mathematicians and university mathematics educators) talk about a multimedia case study on mathematics teaching and learning when they interact both face-to-face and on-line. Also, the researchers compare on-line and face-to-face discussions. Initial findings indicate that both on-line and face-to-face discussions of the case study promoted questioning, answering and informing among the participants. [For complete proceedings, see ED500859.]