Given the growth in popularity of IM, scholars have begun to examine its influence on the workplace (e.g., de Vos, Hofte, & de Poot, 2004; Handel & Herbsleb, 2002; Herbsleb, Atkins, Boyer, Handel, & Finholt, 2002; Isaacs, Walendowski, Whittaker, Schiano, & Kamm, 2002; Muller, Raven, Kogan, Millen, & Carey, 2003; O’Neill & Martin, 2003). A core theme in this body of work is the effects of IM on interruption levels, since IM might be an important new source of such interruptions (Czerwinski, Cutrell, & Horvitz, 2000a, 2000b; Nardi, Whittaker, & Bradner, 2000; Renneker & Godwin, 2003). This view is grounded in the idea that IM supplements existing communication technologies, resulting in an increase in overall communications during work. However, at least some evidence exists that IM is used as a substitute for other media, rather than as an addition, both in work environments (Muller et al., 2003) and social settings (Flanagin, 2005).
A more central way in which IM and work interruptions are related is that IM is interruptive by definition. Interruption has been defined as “a synchronous interaction which is not initiated by the recipient, is unscheduled, and results in the recipient discontinuing their current activity” (O’Conaill & Frohlich, 1995, as cited in Renneker & Godwin, 2003, p. 155). Several characteristics of IM seem directly related to this conception of interruption as a disruption (Renneker & Godwin, 2003). First, the mechanism of message notification is uniquely disruptive. While email clients generally offer users peripheral notification of incoming messages, many commonly-used IM clients default to a high-profile announcement in the form of an immediate on-screen display that appears on top of currently running applications. Second, although IM clients generally provide some form of presence awareness, this tends to be a rather blunt measure of availability. Even when users are able to specify their level of availability (“available,”“do not disturb,” etc.), most users do not assign or frequently update these status indicators, leaving themselves open to uncontrolled interruption. Third, IM might encourage polychronic communication—that is, it might contribute to an environment in which people frequently engage in multiple simultaneous conversations. Such practices could greatly reduce workers’ opportunities to focus on the task at hand. Thus IM’s popularity and its unique technical characteristics would contribute to an increase in the level of interruption in the workplace.
Although increasing levels of interruption are a source of concern for obvious reasons, it is important to note that not all forms of interruption are detrimental, and certain interruptions are a valuable component of work for many. For example, managers often prefer the timely if disruptive delivery of critical information over delayed delivery, because it allows them to make more informed decisions and to intervene before an issue in the work domain becomes unmanageable (e.g., Hudson, Christensen, Kellogg, & Erickson, 2002). Furthermore, not every “interruption” is disruptive. When interruptions pertain to the current work tasks, they may be viewed as valuable opportunities for interaction, information sharing, and coordination. And while interruption during higher-order activities is problematic (e.g., switching from one project to another), routine or familiar work can often be interrupted without much harm to performance (González & Mark, 2004; Mark et al., 2005).
IM as Interruption Management
As suggested by the opening quote from Nardi et al. (2000), there is some evidence that IM might allow people to manage disruptive interruptions more effectively. As noted above, telephone calls and in-person conversations are among the most common sources of interruption. People who initiate such interactions might try to avoid disrupting their coworkers. For example, when working in close proximity, people will listen to their colleagues in order to determine their availability, only interrupting when they think that it will be convenient (Mark et al., 2005, p. 325). However, such strategies are imprecise and prone to error, and they are not effective when people are physically distant, as is the case in most telephone calls.
Nardi and her colleagues (2000) suggest that IM actually provides increased opportunities for negotiating the timing of interactions. From the sender’s point of view, IM provides a relatively unobtrusive way to test availability. The sender does not need to be as concerned about when to initiate communication, because he or she knows that the recipient can ignore or dismiss the IM notification easily or can provide an explicit indication of status quickly (e.g., “I’m busy right now. Can we talk in 15 minutes?”). Although an IM pop-up is disruptive, it is not as distracting as an inopportune telephone call or an unexpected office visit.
From the recipient’s point of view, IM provides two key techniques for managing availability. First, unlike a telephone, IM allows users to flag their availability. Research shows that people can effectively use such information to time interruptions so as to minimize adverse influence on performance (Dabbish & Kraut, 2003). Even if users do not utilize the flags provided by IM software, they can indicate availability in other ways. As noted above, they might request to postpone the conversation. Also, because the presence awareness functionality provided by IM clients is generally quite limited, ignoring an incoming IM is often socially acceptable. Thus IM offers the recipient “plausible deniability” (Nardi et al., 2000, p. 84), because a non-response might simply mean that the person is away from the computer.
New patterns of communication afforded by IM can also be used to manage interruption. IM provides a means of obtaining task relevant information rapidly and with minimal disruption, allowing a worker to ask clarifying questions without the expectation of engaging in a longer conversation. Alternatively, it can be used to participate in a sustained form of low-intensity collaboration (Nardi et al., 2000). Setting up a line of communication via IM is as easy as making a phone call, and the line can be kept open indefinitely, allowing participants to query one another infrequently on an as-needed basis and with the expectation that a response will be forthcoming at the next convenient opportunity. Of course, such communication patterns also depend on the supporting social skills and norms of the users, but the technology does afford a novel opportunity. Finally, IM could enable workers to manage their work/life balance less disruptively. Using IM, non-work communications can be integrated seamlessly into the work environment, affording quick, conveniently timed check-ins with family and friends without requiring relatively longer periods of off-task time (e.g., Handel & Herbsleb, 2002; Nardi et al., 2000).
In this article, we analyze empirically the experiences of contemporary U.S. workers with IM. Based on the evidence, we argue that, contrary to prevailing concerns, IM generally does not contribute to higher levels of workplace interruption. While the technology makes certain types of interruption easier, it can also allow users greater control over when to communicate, with minimal disruption to their on-going work, and can afford them the opportunity to create new patterns of communication that sustain necessary linkages while reducing off-task distractions. We suggest that such strategic uses currently dominate. From this perspective, IM might actually serve to reduce overall interruption levels. Although people using IM during work will engage in more frequent communication, we do not anticipate that use of IM will be associated with more communication overall or with more interruption.
Our analysis empirically assesses four hypotheses associated with instant messaging in work environments:
H1: IM users will report lower levels of disruptive interruption than will non-users.
H2: IM users will have the same overall level of work communication as will non-users.
H3a: IM users will engage in more frequent computer-mediated work communication than will non-users.
H3b: IM users will engage in more frequent computer-mediated personal communication than will non-users.
In the following sections, we describe the data used to test these hypotheses, and we report our results. We then conclude that IM use is associated with changing communication patterns and discuss what these results mean for scholars’ and professionals’ understanding of instant messaging in the workplace, as well as how this might change as IM clients evolve to include other communication modalities, such as voice or video.