Oils of animal, mineral and vegetable origin are used in the formulation of pharmaceuticals. In most cases the analysis of these pharmaceuticals requires the separation of the drug substance from the oil components prior to its quantitation, the required degree of separation depending on the specificity of the quantitation method. When the physical properties of the drug substance are quite similar to those of components of the oil, the separation of the drug becomes complex. Column partition chromatography provides an excellent means of separating steroids from the vegetable oil vehicles used in injectables. Both reverse phase and direct phase techniques are applied to the separation of the steroids from the glyceride, stern and triterpenoid fractions of the oil. Illustrations are provided to demonstrate the application of thin layer chromatography, paper chromatography, gas chromatography, gel permeation chromatography and adsorption chromatography in the analysis of oil solutions, oil-based dermatological preparations and suppositories.