This book presents current research and development work in the fields of knowledge visualization and information visualization. In addition to revised reviewed papers presented at an international workshop on Visual Artefacts for the Organization of Information and Knowledge held in Tübingen, Germany in May 2004, invited papers from leading experts are included to round off coverage of relevant aspects.The 19 chapters presented together with an introductory overview are organized in topical sections on background, knowledge visualization, information visualization, visualizing knowledge and information for fostering learning and instruction, and knowledge-oriented organization of information for fostering information use.