(From the NSA Handbook)
Classified information is disseminated only on a strict "need-to-know" basis.
The "need-to-know" policy means that classified information will be
disseminated only to those individuals who, in addition to possessing a proper
clearance, have a requirement to know this information in order to perform
their official duties (need-to-know). No person is entitled to classified
information solely by virtue of office, position, rank, or security clearance.
All NSA personnel have the responsibility to assert the "need-to-know" policy
as part of their responsibility to protect sensitive information.
Determination of "need-to-know" is a supervisory responsibility. This means
that if there is any doubt in your mind as to an individual's "need-to-know,"
you should always check with your supervisor before releasing any classified
material under your control.