Todays communication systems consist of a bewildering array of devices and technologies. Mobile phones, PDAs, personal computers, corporate servers, Internet sites, even wearable devices -- all of these compete for our attention and require us to interact with them in different ways. A Multiple User Interface (MUI) helps with this variety of communication systems and devices by offering a coherent, integrated user experience across platforms. A MUI manages and coordinates services provided to the user through multiple devices and platforms. In addition, it adapts the view of the information to the computing platform in use. The authors, who represent a wide range of research expertise in both industry and academia, introduce design and development frameworks for multi-device, cross-platform and context-aware systems. These frameworks are valuable to researchers and practitioners in usability and software engineering, and to anyone interested in the problem of developing and evaluating MUIs. Designers and developers, students and educators will find this book useful for its applied and theoretical content, supported by well-established HCI (Human-Computer Interaction) methodologies. The following questions and more are addressed in Multiple User Interfaces:What kinds of design methods are needed for building MUIs? How can we enable users to customise a device? How can the customisation of one device be reflected on all of the other devices available to the user? What is the best way to deal with device-specific constraints while assuring maintainability and cross-platform consistency of interfaces? How can we build interfaces that dynamically respond to changes in the environment, such as variations in network connectivity, user location, ambient sound and lighting conditions?