This paper presents a detailed examination of factors that affect perceptions of and attitudes towards multitasking in video conferencing. We first report findings from interviews with 15 professional users of videoconferencing. Our interviews revealed the roles and potential link of technology and activity. We then report results from a controlled online experiment with 397 participants based in the United States. Our results show that the technology used for multitasking has a significant effect on others’ assumptions of what secondary activity the multitasker is likely engaged in, and that this assumed activity in turn affects evaluations of politeness and appropriateness. We also show that different layouts of the video conferencing UI can affect perception of engagement in the meeting and in turn ratings of polite or impolite behavior. We propose a conceptual model that captures our results and use the model to discuss implications for behavior and for the design of video commu...