Knowledge on PRRS transmission is still lacking, but management strategies exist to control it. The strategy that will be most effective differs between barns based on location (if the area is hog-dense or not), herd health status, herd immunity, and strain of PRRS. Acute outbreak management strategies include implementing the McREBEL fostering system, strict all-in all-out protocol, and uniformly infecting the herd to gain immunity. Endemic PRRS persist in the nursery and finisher stages for long after the initial outbreak. The virus can be spread horizontally or vertically, and the source should be identified as soon as possible. Total or partial depopulation, strict all-in all-out, thorough sanitation and disinfection procedures, and vaccination are methods to eliminate endemic PRRS. Long-term control of PRRS is primarily strict biosecurity: the source of the initial outbreak should be located and fixed, and any other lacking areas fixed as well. New gilts should be isolated and acclimatized before herd entry, mass vaccination can be used, and herd closure or depopulation/repopulation can be used for long-term control.