This chapter discusses how language technology is used to control the volume of interpersonal communication. It examines a range of language technologies that have increasingly empowered individuals to call the shots on social interaction. The more conceptual discussion is illustrated with data from a study undertaken in fall 2004 and spring 2005 of multitasking behavior by college students while using instant messaging. The study reveals how deft the current generation of multitaskers is at meshing online conversations with other activities. In electronically-mediated communication, users turn up the “volume” when they incessantly check their email. Along with the volume-control metaphor, another useful concept is affordances, the physical properties of objects that enable us to use them in particular ways. This chapter also looks at discourse control in traditional face-to-face and written-communication settings, and then at the affordances new language technologies add for adjusting the conversational “volume”. The cognitive and social aspects of multitasking, specifically with respect to instant messaging and mobile phones, are also discussed.