This book gathers the latest experience of experts, research teams and leading organizations involved in computer-aided design of user interfaces of interactive applications. This area investigates how it is desirable and possible to support, to facilitate and to speed up the development life cycle of any interactive system: requirements engineering, early-stage design, detailed design, development, deployment, evaluation and maintenance. In particular, it stresses how the design activity could be better understood for different types of advanced interactive systems such as context-aware systems, multimodal applications, multi-platform systems, pervasive computing, ubiquitous computing and multi-device environments.