For the past 5 years the Bureau of Mines at Rifle, Colorado has conducted experimental work on the thermal processing of shale oil and the chemical treating of distillate products. This work was completed at the end of June 1954. Although the large volume of data has not yet been assimilated and evaluated, this paper summarizes in a general way our current conclusions from the work. Before discussing the refining work it is desirable to have in mind the physical and chemical properties of Colorado shale oil. Some of the properties of Colorado shale oil is in the heavy oil class, about 20 API gravity, and contains almost no material in the gasoline boiling range. Its pour point and viscosity are high, making it difficult to handle without heating. Actually, some treatment to reduce the pour point is required to make long distance pipeline transportation practical.