A primary responsibility of the boar stud is to transfer genetics via fertile sperm to the down stream sow farms. There is an expectation that this will occur without transferring infectious disease. Ironically, the widespread adaptation of boar studs to disseminate fertile sperm and genetics has paralleled the evolution of viruses such as porcine reproductive and respiratory syndrome virus (PRRS), that may transmit through the semen and infect sow farms. Biosecurity measures to prevent PRRS virus transfer among farms has largely influenced the biosecurity practices of boar studs in North America and worldwide. It is important to understand which factors are most important and to keep staff focused on the most important risks, while not becoming side-tracked on procedures that have little impact.