Sure.
There have been a couple of mentions already of the Federal Accountability Act and the designation of deputy heads as accounting officers. One of the things that accounting officers are responsible for is control, and another one is compliance with government policies. There are other things as well.
An easy way to understand internal audit, I would say, is that it's a source of information targeted towards the deputy heads to give him or her assurance about whether the control systems or compliance policies that he or she is ultimately accountable for are in fact in place and working. It gives them an early warning, if there are any signs of trouble, to remediate things.
So it's a management tool. It's focus is on improving control and compliance, and it is in support of the deputy head's role as an accounting officer.