[a]n official inquiry into the activities of a person designed to develop information from a review of the records, one or more interviews of the subject, and interviews of people having knowledge of the subject.
U.S. federal government
A background investigation is
[a] personnel investigation conducted to meet the requirements of EO 10450 and, when applicable, EO 12968.
[a] personnel security investigation consisting of both record reviews and interviews with sources of information covering the most recent 5 years of an individual's life, or since the 18th birthday, whichever is shorter, provided that at least 2 years are covered and that no investigation will be conducted prior to an individual's 16th birthday.