In recent decades technology-induced interruptions emerged as a key object of study in HCI and CSCW research, but until recently the social dimension of interruptions has been relatively neglected. The focus of existing research on interruptions has been mostly on their direct effects on the persons whose activities are interrupted. Arguably, however, it is also necessary to take into account the "ripple effect" of interruptions, that is, indirect consequences of interruptions within the social context of an activity, to properly understand interrupting behavior and provide advanced technological support for handling interruptions. This paper reports an empirical study, in which we examine a set of facets of the social context of interruptions, which we identified in a previous conceptual analysis. The results suggest that people do take into account various facets of the social context when making decisions about whether or not it is appropriate to interrupt another person.