Total cholesterol and triglyceride concentrations in 127 samples of capillary and venous blood were measured with the portable Reflotron 'dry chemistry' reflectometer and compared with serum levels measured in the laboratory using wet chemistry methods. Results were grouped into low, middle and high ranges. Levels measured with the Reflotron correlated closely with those measured by wet chemistry methods. Reflotron values for both lipid fractions were, however, consistently higher than wet chemistry levels but the differences were small except at high levels. It is concluded that the Reflotron is a satisfactory instrument for providing clinically useful measurements of cholesterol and triglyceride nearer to the patient.