This book is the formal proceedings of the Eurographics Workshop on Design, Specifi cation and Verification ofInteractive Systems, DSV-IS'99, which was held at the Uni versity of Minho, Braga, Portugal from June 2 to June 4, 1999. The previous events of this series were held at Pisa, Toulouse, Namur, Granada, and Abingdon; the theme this year was "Engaging the Mind by Enriching the Senses," emphasising the importance of the interface in making interaction both effective and enjoyable. Presentations and discussions covered topics that included specification methods and their use in design,...