How do discursive differences between legal professionals and jurors affect courtroom decisions? How does the DSM-III - the American Psychiatric Association's taxonomy of mental disorders - shape psychiatric practice? How can a narrative of social progress shape scientific theory? How do conflicting problem-solving strategies within a community contribute to technological disasters like Three Mile Island and the Shuttle Challenger? This book is a collection of 15 essays examining the real effects of texts on professional practice - in academic, scientific, and business settings. The authors describe textual dynamics as an interaction in which professional texts and discourses are constructed by, and in turn construct, social practices. This anthology treats a wide range of professional texts including case studies, student papers, medieval letters and product instructions.