Today’s Internet users expect to access Internet resources using increasingly capable and ubiquitous client platforms. This trend has resulted in a wide-ranging diversification of hardware devices supporting various form factors and interaction modes, a choice of web browsers offering varying levels of performance, security and standards compliance, as well as the emergence of domain-specific uses of general-purpose Internet-related technologies, exemplified by Rich Internet Applications (RIAs) and site-specific browsers. Despite the heterogeneity, all these platforms implement a common set of standards and technologies. While the resulting high level of interoperability can be seen as a major reason for the Internet’s success, its constraints can also be viewed as limiting progress in client technologies. This workshop focuses on both innovative solutions in the area of Internet client software that improves on the current state-of-the-art while respecting the confines dictated by interoperability, as well as bold, new ideas that break with the status quo.