The CIA has opened an investigation into the conduct of its former director David Petraeus, who resigned last week citing an affair with his biographer.
A CIA spokesman says the inquiry by the agency's inspector general would see if there are any lessons to be learned.
Paula Broadwell, 40, was found to have classified information, but both she and Gen Petraeus deny it came from him.
Gen Petraeus will testify on Friday on Capitol Hill about September's deadly attack on the US consulate in Libya.
The CIA said in a statement on Thursday: "At the CIA we are constantly reviewing our performance. If there are lessons to be learned from this case we'll use them to improve.
"But we're not getting ahead of ourselves; an investigation is exploratory and doesn't presuppose any particular outcome."
In his first interview since resigning, Gen Petraeus told CNN on Thursday he had not given any classified information to his former lover.
He also said he quit because of the affair, not the assault two months ago on the consulate in Benghazi that left four Americans dead.
Gen Petraeus will be questioned by lawmakers behind closed doors on Friday about that attack, which has been the focus of Republican claims that the Obama administration misled the American people.