CIA launches big internal review

• The CIA director launched an agency-wide review of structure and business practices


• The review was launched in September, but was just reported


• Currently the CIA is broken into four different divisions

Washington (CNN) -- CIA Director John Brennan has ordered an in-depth review of the intelligence agency's organizational structure, asking the agency to "take a close and honest look at ourselves."

Citing an "ever-growing number" of complex national security challenges as cause for the evaluation, Brennan announced the internal review in a letter to Central Intelligence Agency staff. The CIA released unclassified portions of the letter on Thursday.

The review will come as the CIA adapts to new threats from terror groups like ISIS and the al Qaeda linked Khorasan group have added to agency's terror landscape.

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"I have mentioned several times over the past year that I have become increasingly convinced that the time has come to take a fresh look at how we are organized as an Agency," Brennan wrote in the letter dated September 24, 2014. He added that the review will examine the CIA's structure and "ways of doing business."

Officers leading the review are tasked with looking at ways to integrate the sprawling intelligence agency. The organization is currently split into four major divisions. The clandestine staff that collects intelligence information, for instance, is separate from the staff analyzing the data collected.

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"The need for integration has never been greater," Brennan wrote. "The complex national security issues we face today, and the extent to which those issues cross geographic and functional boundaries, challenge our ability to leverage the entire breadth of capabilities the CIA has to offer."

A proposal to split the agency into subject matter divisions where analysts and clandestine officers work together, as reported by the Washington Post, is not yet formal, according to the CIA.

"Given that the review is still pending, the officers have not yet put forth their findings, conclusions or recommendations," said CIA spokesman Dean Boyd.