The light - a mysterious, weightless, almost non-material substance, that surrounds all of us, that brings the peace of the day at every dawn, that extends the space around us, making it accessible to our senses and that impacts our life, activity and esthetic sensations. The symbol of divinity, life, truth and beauty. A force that guarantees life throughout the Earth's entire biosphere. Human civilization is a history of the man's struggle to control and subdue light: the first camp fires, torches, cressets, candles, kerosene lamps and at the end all possible kinds of electric lamps, each one more efficient than the previous one - such are the stages of the rise of our civilization. Our efforts yield increasingly spectacular results. Our current, very efficient light sources let us disregard the rule of day and night. Not only can we freely shape our light environment, but also use the light to send information, cure ailments and enhance our esthetic sensations.This book contains papers presented and the first International Conference on Lighting in Engineering, Architecture and the Environment, held in Poznan, Poland, 2011, where scientist dealing with lighting technologies, architects and experts in other fields of science and art related to the use of light met. The meeting was a chance for an in-depth discussion on various aspects of the use of light for all kinds of technological purposes, art, medicine and environment. The subject areas discussed include: Architectural Lighting Design and Applications; Illumination of Architectural Objects; Outdoor Lighting; Indoor Lighting Design and Applications; Light and Human Health.