Rodger AJ, et al. - Via the second phase of the PARTNER study (PARTNER2, a prospective observational study) done at 75 sites in 14 European countries with 972 gay couples, the researchers intended to provide exact estimates of transmission risk in gay serodifferent partnerships. The risk of HIV transmission in gay couples through condomless sex when HIV viral load is suppressed was effectively concluded as essentially zero. Hence, a similar level of evidence on viral suppression and HIV transmission risk for gay men that was previously generated for heterosexual couples was noted. The benefits of early testing and treatment for HIV and the message of the U=U (undetectable equals untransmittable) campaign was supported by the findings.