This book is about how people (we refer to them as practitioners) can help guide participants in creating representations of issues or ideas, such as collaborative diagrams, especially in the context of Participatory Design (PD). At its best, such representations can reach a very high level of expressiveness and usefulness, an ideal we refer to as Knowledge Art. Achieving that level requires effective engagement, often aided by facilitators or other practitioners. Most PD research focuses on tools and methods, or on participant experience. The next source of advantage is to better illuminate...