Light is essential for living organisms; however, excessive light causes adverse health conditions. This book covers the most recent progress on nanotechnology for reducing light pollution, discussing many approaches and technologies for controlling light pollution. The book explores the fundamentals of light and the causes of light pollution, delving into light pollution’s social, economic, and ecological impacts, its effects on living beings and the environment, as well as possible solutions and methods of control. The text discusses smart lighting technology, covering the various smart nanomaterials, nanosensors, and nanodevices involved. It also explores smart lighting involving natural light from the sun, artificial skydomes, shadow-free/secondary light sources, and the basics of many emerging devices such as light-emitting diodes and photosensors. Nanotechnology is key to providing a new route for the next generation of lighting devices and systems with reduced light pollution. This essential reference illuminates emerging technologies and their applications, providing new directions to scientists, researchers, and students to better understand the principles, technologies, and applications of nanotechnology in light pollution.