need to know, need-to-know

The necessity for access to, knowledge of, or possession of specific information required to carry out official duties.

Usage: The compound "need-to-know" is commonly used as either an adjective or a noun.

Tutorial: The need-to-know criterion is used in security procedures that require a custodian of sensitive information, prior to disclosing the information to someone else, to establish that the intended recipient has proper authorization to access the information.