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, model-based tool support, task and dialogue models, distributed col laboration, and models for VR input. As in previous years, there was a strong emphasis on formal representations and modelling techniques, and their use in understanding in teraction and informing the design of artefacts. However, the aim of the workshop is to encourage an exchange of views within a broad community, and other approaches, in particular tool support for model-based design, were also represented. This book includes the papers of the two invited speakers (one as an abstract only), the fourteen full papers accepted for publication, two shorter position papers, and the reports from the working group discussions. The format of the workshop aimed to mix formal paper presentations with informal discussion sessions, with the two invited talks setting the tone for the meeting."