This paper investigates the impact that a teacher's virtual presence--or lack thereof--has on students' chat behavior with regard to error correction, uptake, target language use, and on-task behavior. The data come from beginning German students engaged in pair and small-group chatting activities at a major American university. Transcripts from chat sessions in a first-semester German class and a second-semester German class were analyzed. The data were triangulated with student surveys and teacher interviews. Results suggest that the teachers' participation styles had a greater influence on learners' chat behavior than simply whether or not the teachers were present and that the form-focused participation style of one of the teachers had an apparently inhibitory effect on learner participation. (Contains 1 figure, 9 tables and 1 note.)