Cyclododecane was introduced to conservation in 1995 and has since proved to be a versatile and useful conservation material. It has been used on a wide variety of materials, including wall paintings, plaster, ceramics, paper, textiles and metals. Its ability to sublime without residues is particularly exciting for conservators because it offers the possibility of a temporary consolidant, binding medium, adhesive or support material that is fully reversible. This paper describes the ways in which cyclododecane has been used in conservation, and offers a detailed sure y of its properties and behavior in various conditions. The health and safety information is also thoroughly reviewed; this is especially useful because the information in the conservation literature is frequently confused or inaccurate. Conservators should always take thorough precautions to protect themselves against inhalation of cyclododecane until more is known about its effect on human health.