FromMay28toJune1,2007,aseminaron¿InformationVisualization¿Human- Centered Issues in Visual Representation, Interaction, and Evaluation¿ ( 07221) took place at the International Conference and Research Center for Computer Science, Dagstuhl Castle, Germany. The center was initiated by the German government to promote informatics research at an international level. It seeks to foster dialog among the computer science research community, advance a- demic education and professional development, and transfer knowledge between academia and industry. The primary feature of Dagstuhl is its series of week-long seminars on v- ious topics in computer science. Dagstuhl seminars are frequently described as being the mostproductive academic events that the participantresearchershave ever experienced. The informal and friendly atmosphere fostered at the center promotes personal interaction between the guests. Traditionally, there is no set programfollowedat Dagstuhl seminars.Instead, the pace and the procedure are determined by the presentations o?ered during the seminar and the discussion results. Further general information about Dagstuhl seminars can be found on 1 the Dagstuhl Castle webpage . Information visualization (InfoVis) is a relatively new research area, which focuses on the use of visualization techniques to help people understand and analyze data. While related ?elds such as scienti?c visualization involve the p- sentation of data that has some physical or geometric correspondence, infor- tionvisualizationcentersonabstractinformationwithoutsuchcorrespondences, i.e., information that cannot be mapped into the physical world in most cases.