Interaction designers and software engineers design interactive systems under different yet complementary perspectives. It is necessary, however, to build bridges between the two areas, so that both professionals may contribute with their own expertise to the quality of the final product. One way to foster this communication is by means of shared representations. This paper presents a qualitative study that investigated the use of a set of HCI design representations as a boundary object to convey to software engineers the interaction design solution in the form of a blueprint of the application’s apparent behavior.