Informal interactions are a key element of group work, and many theoretical frameworks and systems have been developed to understand and support these conversations in distributed workgroups. In particular, systems used in several recent experiments provided information about others' current activities so that their availability for conversation could be assessed, and interruptions could be timed strategically. One issue with these experimental systems, though, is that many do not notify the observed party that these observations are taking place. There is reason to believe that such notification could be valuable to users, and that it could alter observers' behavior. Moreover, factors such as the perceived urgency of the interruption could affect willingness to violate social norms in gathering information. We report on an experiment assessing the impact of perceived visibility and task urgency on awareness checking behavior. Results suggest that people check more often when they believe their partners do not know they are checking, and more often when the task is time-constrained than when it is not.