This volume contains a selection of refereed papers from participants of the workshop "Construction and Analysis of Safe, Secure and Interoperable Smart Devices" (CASSIS), held from the 10th to the 13th March 2004 in Marseille, France: http: //www-sop.inria.fr/everest/events/cassis04/ The workshop was organized by INRIA (Institut National de Recherche en InformatiqueetenAutomatique), Franceandthe UniversitydelaM editerran ee, Marseille, France. The workshop was attended by nearly 100 participants, who were invited for their contributions to relevant areas of computer science. Theaimoftheworkshopwastobringtogetherexpertsfromthesmartdevices industry and academic researchers, with a view to stimulate research on formal methods and security, and to encourage the smart device industry to adopt innovative solutions drawn from academic research. The next generation of smart devices holds the promise of providing the required infrastructure for the secure provision of multiple and personalized services. In order to deliver their promise, the smart device technology must however pursue the radical evolution that was initiated with the adoption of multi-application smartcards. Typical needs include: - The possibility for smart devices to feature extensible computational infr- tructures that may be enhanced to support increasingly complex appli- tions that may be installed post-issuance, and may require operating system functionalities that were not pre-installed. Such additional ?exibility must however not compromise security. - The possibility for smart devices to achieve a better integration with larger computersystems, throughimprovedconnectivity, genericity, aswellasint- operability."