The reactivity of Immunoglobulin Binding Proteins (IBP) to Fc and/or Fab fragments of immunoglobulins was summarized in this review. Staphylococcal protein A (SpA), Streptococcal protein G and Peptostreptococcal protein L (SpL) were the IBP reported. SpA reacted with IgG from skunk, coyote, raccoon, mule and donkey. SpG reacted almost with the entire panel of immunoglobulins and SpL binding was restricted to some immunoglobulins including raccoon, ostrich and duck. The various immunological techniques that have been used to test the binding capacity of IBP to Igs were double immunodiffusion, Enzyme-Linked Immunosorbent Assay (ELISA), SpA-affinity chromatography and immunoblot analysis. These protein-protein interactions are important because they can be used in the immunodiagnosis and in the purification of intact Igs or their fragments.