Book excerpt: Written by international researchers in the field of Distributed User Interfaces (DUIs), this book brings together important contributions regarding collaboration and usability in Distributed User Interface settings. Throughout the thirteen chapters authors address key questions concerning how collaboration can be improved by using DUIs, including: in which situations a DUI is suitable to ease the collaboration among users; how usability standards can be used to evaluate the usability of systems based on DUIs; and accurately describe case studies and prototypes implementing these concerns. Under a collaborative scenario, users sharing common goals may take advantage of DUI environments to carry out their tasks more successfully because DUIs provide a shared environment where the users are allowed to manipulate information in the same space and at the same time. Under this hypothesis, collaborative DUI scenarios open new challenges to usability evaluation techniques and methods. Distributed User Interfaces: Collaboration and Usability presents an integrated view of different approaches related to Collaboration and Usability in Distributed User Interface settings, which demonstrate the state of the art, as well as future directions in this novel and rapidly evolving subject area.