The book presents modern issues of the evolution of artificial lighting, changes in shape (pattern) of spectral-energy characteristics of light and their influence on functioning of human visual analyser, its health, health of subsequent generations and environment, creation of optimal colour and light environment at workplaces of main professions, preventive measures aimed at reduction of general and visual fatigue in process of work, basic laws of light hygiene are formulated. The book is intended for hygienists, occupational pathologists, ophthalmologists, labor protection specialists, doctors of medical and social expertise, students of medical and technical universities.