Summary: Emulsions are gaining in popularity. They fulfill a need: low cost materials for quality construction and maintenance. Asphalt emulsions are widely used for every phase of bituminous application. Several years ago emulsions were used occasionally. Interest for emulsions was kindled during the oil crisis in the early 1970’s. Other factors made emulsions take on a new importance. Emulsions are stored and handled at or near ambient temperatures and therefore save fuel required for heating. The new emulsion technology permits the use of many types of aggregates. The risk of fire hazard is slight because of the composition of the emulsion, and emulsions are environmentally clean because they emit hydrocarbons.