Imagine a world where your clothes sense your blood pressure, heart rate and body temperature. Suppose the sensors transmit this information to the cloud , continuously and unobtrusively. Suppose artificial intelligence in the cloud detects an anomaly. Suppose it tells your doctor: sighs of relief all round. But then suppose it tells an actuary, who tells your insurer, who tells your employer ... This is the world of pervasive adaptation. This Pervasive Day explores the potential and perils of daily living with pervasive adaptive computing. This is the result of saturating ourselves and our physical environment with sensors, cameras and devices, all connected to and inter-connected by global networks and computers, which can run increasingly intelligent machine-learning and data fusion algorithms on datasets that could be generated by the entire human population. This book takes as its unifying theme Ira Levin's 1970 science fiction novel This Perfect Day to expose both potential innovations and controversial social issues. It explores the science and technology of pervasive adaptation through a human-centred and socio-technical perspective within the cultural, ethical and legal context of contemporary life. It discusses how pervasive adaptation could provide the foundations for a new range of life-enhancing and planet-saving applications in health, sustainability and assistive living. On the other hand, with the recording, storage and processing of every action, emotion and thought, there also arise the possibilities for unwarranted surveillance, invasions of privacy, loss of civil liberties and commercial exploitation. This Pervasive Day is an insightful read for anyone concerned with the social impact of technology. Written by experienced technologists with a deep interest in computational intelligence, human-computer interaction and ambient systems, This Pervasive Day is a remarkable single source of reference a fusion of several technical disciplines that makes for a broad scope of investigation within the domains of pervasive computing. Unifying, informative and thought-provoking, This Pervasive Day takes its place as a landmark title that will challenge the perceptions of the technologists and policy-makers, the pragmatists and the theorists, the doers and the thought-leaders.