Converting coal to a liquid, commonly known as coal-to-liquids (CTL), can supply liquid fuels and has been successfully used in several countries, particularly in South Africa. However, it has not become a major contributor to the global oil supply. Increasing awareness of the scarcity of oil and rising oil prices has increased the interest in coal liquefaction. This paper surveys CTL technology, economics and environmental performance. Understanding the fundamental aspects of coal liquefaction technologies is vital for planning and policy-making since future CTL production will be integrated in a much larger global energy and liquid fuel production system.