Under the guidance of John Krumm, a ubiquitous computing pioneer, this book brings together eleven ubicomp trailblazers who report on their area of expertise. Starting with a historical introduction, it moves on to summarize a number of topics-from the application of quantitative methods to ubiquitous systems software. Taking a decidedly human perspective, the book explains how to observe people in their natural environments and evaluate the critical points where ubiquitous computing technologies can improve their lives.