If you are interested in understanding how the systematic use of task models in the design, development, and usability evaluation of interactive software applications can open new opportunities and possibilities then this book will help you do just that. Fabio Patern� also discusses related issues relevant to designing user interfaces and provides a state-of-the-art review of the field, including recently developed methods, current results and problems and trends. Details of the notation and analysis discussed, including case studies of industrial interest, are available for those who want to use them for applied projects and in industrial contexts. While the book is designed to suit a range of academic and industrial courses on task models and methods for user interface design and evaluation, it will also be useful as supplementary reading for any course on human-computer interaction and software engineering.