Overhearing has been proposed recently as a model of indirect interactions in Multi-Agent Systems, Overhearer agents receive messages that were not primarily sent to them, as when someone hears a conversation among others. Overhearing has been modeled essentially as message broadcasting, but this approach raises several issues of seal-ability and appropriateness of the mental state of overheard agents. In this paper, we motivate and propose & model of overhearing that copes with these issues by introducing an explicit environment entity to handle overhearing. We define key notions with focus on the environment perspective, model them and their relations, and detail an algorithm that describes the environmental process for agent interactions. We finally illustrate our approach with an electronic market scenario.