On line and on paper : visual representations visual culture and computer graphics in design engineering Henderson shows how designers use drawings both to organize work and knowledge and to recruit and organize resources political support and power. This analysis of the collective nature of knowledge in technical design work is based on her participant observation of practices in two industrial settings. In one she follows the evolution of a turbine engine package from design to production and in the other she examines the development of an innovative surgical tool. In both cases she describes the messy realities of design practice including the mixed use of the worlds of paper and computer graphics. One of the goals of the book is to lay a practice informed groundwork for the creation of more usable computer tools. Henderson also explores the relationship between the historical development of engineering as a profession and the standardization of engineering knowledge