The apparent and corrected digestibilities of beef tallow, H.E.F. and soyabean oil have been determined in the newly weaned pig. Determinations of the individual fatty acids in the food and faecal lipids allowed the digestibility of each acid to be calculated separately. The purest available forms of oleic, stearic and palmitic acids and their corresponding triglycerides were also used in the determination of digestibility. Although the digestibility of each fatty acid is to some extent a characteristic of the acid, the extent of absorption can also be modified by the other acids in the diet. The results.of these experiments give no clear indication of a difference between feeding fatty acids in the free form or as the triglycerides. The digestible energy values of the fats have been calculated as the product of gross energy value and corrected digestibility.