Personnel Security is an important part of Information Assurance, risk management and information security. Its a part of the equation that happens in the background.
Personnel security is to ensure that everyone with security responsibilities at the organizations site meet the trustworthiness investigative levels for users with IA management access to defense information systems. This is as established in Section E3.4.8 of DoDI 8500.2.
Personnel security makes sure that only individuals who have a valid need-to-know that is demonstrated by assigned official government duties and who satisfy all personnel security criteria. This includes people with administration rights and those doing sensitivity background investigation requirements since they are granted access to information with special protection measures or restricted distribution as established by the information owner. All individuals requiring access to classified information are processed for access authorization in accordance with DoD personnel security policies. This includes maintenance personnel, since they also need to be cleared to the highest level of information on the system.
Personnel security is an important job for making sure that the right people are hired to handle sensitive information.