The International Day of Light is a global initiative that provides an annual focal point for the continued appreciation of light and the role it plays in science, culture and art, education, and sustainable development, and in fields as diverse as medicine, communications, and energy. The broad theme of light will allow many different sectors of society worldwide to participate in activities that demonstrates how science, technology, art and culture can help achieve the goals of UNESCO – education, equality, and peace. The International Day of Light will consist of coordinated activities on national, regional and international levels. Activities will be planned so that people of all ages and all backgrounds can gain an appreciation for the central role of light in science and culture, and as a cross-cutting scientific discipline that can advance sustainable development.