In clinical andrology, the detection of antisperm antibodies (ASA) is regarded as one of the most important steps in the study of male infertility. This practice is generally accepted even though there is still some disagreement about the true meaning of antisperm immunity, and there remains a good deal of controversy about the test regarded as the most suitable for the detection of antibodies directed against sperm antigens. International Workshops have tried to standardize universally accepted protocols. A panel of three or four methods is generally advised to provide a correct and complete screening of patients with antisperm immunity. The aim of the present paper is to report our studies on the correlation between direct methods (IBT, MAR test) and indirect methods (gelatin agglutination test [GAT], and tray agglutination test [TAT]) and to establish whether biological models can explain the antibody test results. An attempt was also made to establish a "predictive threshold" to explain even apparently discordant direct and indirect results.