What happens in an established practice or work setting when a novel artifact or tool for doing work changes the familiar work routines? Any unexpected event, or change, or technological innovation creates a discontinuity; organizations and individuals must reframe taken-for-granted assumptions and practices and reposition themselves. To study innovation as a phenomenon, then, we must search for situations of discontinuity and rupture and explore them in depth. In Shifting Practices, Giovan Francesco Lanzara does just that, and discovers that disruptions and discontinuities caused by the introduction of new technologies often reveal aspects of practice not previously observed.After discussing methodological and research issues, Lanzara presents two in-depth studies focusing on processes of design and innovation in two different practice settings: music education and criminal justice. In the first, he works with the music department of a major American university to develop Music LOGO, a computer system that allows students to explore musical structures with simple, composition-like exercises and experiments. In the second, he works with the Italian court system in the design and use of video technology for criminal trials. In both cases, drawing on anecdotes and examples as well as theory and analysis, he traces the new systems from design through implementation and adoption. Finally, Lanzara considers the researcher's role, and the relationship -- encompassing empathy, vulnerability, and temporality -- between the reflective researcher and actors in the practice setting.