An astrolabe is an ancient instrument used to measure the position of the sun and stars. In the past it was used for a number of purposes, such as determining the time of day or night and measuring one’s current position in relation to the north and south poles. A mariner’s astrolabe was used to determine the latitude of a ship at sea and guide its direction. Similar to the mariner’s astrolabe, the Asia-Pacific Education for Sustainable Development (ESD) Astrolabe aims to assist UNESCO Member States in determining the current position of ESD in their country and guiding education and learning in a desired direction, so as to support the advancement of sustainable development in the national context. The ESD Astrolabe is also intended to complement ongoing efforts to enhance the quality of education throughout the Asia-Pacific region.