Cumulative knowledge of the protein composition of plasma and newer techniques for specific analysis of proteins have made obsolete most flocculation tests, the albumin:globulin ratio, scanning diagrams, and most determinations of electrophoretic fractions. More clinically relevant information about the serum protein composition is obtained by critical visual evaluation of the protein bands obtained after electrophoretic separation of plasma or serum in nonadsorptive supporting media, if supplementary specific analysis is made of a small number of proteins such as albumin, orosomucoid, haptoglobins, ceruloplasmin, and the immunoglobulins of the three predominant classes