ALTHOUGH meningococcal disease is presently uncommon in the United States, the suddenness and severity with which it strikes and its epidemic potential frequently produce considerable anxiety in patient contacts. This may lead concerned physicians to take measures that are inappropriate or unnecessary. A recent editorial1 defines in detail the type of contact associated with increased risk and reviews the prophylactic measures appropriate for reducing this risk. However, a study by the Meningococcal Disease Surveillance Group2 indicates that physicians often do not administer antimicrobial prophylaxis to persons at increased risk and do administer prophylaxis to persons not shown to be at risk. The same study showed that when physicians give antibiotics, they often select ineffective ones. Additionally, it showed that considerable time and money are spent doing useless culture surveys of contacts. Because of this evident confusion about who would benefit from meningococcal prophylaxis, about what agents should be