“…This approach is informed by Activity Theory (Kaptelinin, 1996;Kuutti, 1996). In addition to addressing task management in email, other new email interfaces are proposed to better show relationships among messages (Rohall et al, 2001;Sudarsky et al 2002;Venolia and Neustaedter, 2003), to provide message summarization (Rohall and Gruen, 2002) and to exploit social relations among one's correspondents (Farnham 2002, Whittaker et al, 2002. Little is known, however, about how to evaluate these new interfaces and visualizations and how to measure the improvement attributable to them (Gwizdka and Whittaker, 2003).…”