Complex antigen mixtures displayed in Western blots may be immediately and quantitatively categorized with respect to specificity and immunogenicity by immunoplotting. This involves plotting the frequency with which each antigen band reacts with a set of immune sera against the frequency of the same band when reacted with another set of immune sera. Immunoplotting has proven to be a powerful method of analyzing Western blots of reactions between vesicular fluids from the metacestodes of Taenia solium, E. granulosus, and T. crassiceps, and sera from human cases of neurocysticercosis and hydatid disease. Immunoplotting readily sorts out those antigens useful for discriminative immunodiagnosis from the multitude of bands in the sera of sick and healthy people. It aids in assessing the antigenic similarity between the human parasites and the murine parasite T. crassiceps, validating the latter as an alternative source of antigens for immunodiagnosis of cysticercosis and hydatid disease.