The last significant review of staff numbers was a review of the needs of the Committee Office in 2003, conducted jointly by the House’s Internal Review Service (IRS) and the National Audit Office. More generally, staffing levels are controlled by a budgetary mechanism rather than by limits on staff numbers. The IRS has recently completed the first stage of a review of staff grading. Subject to the views of the Administration Estimate Audit Committee, the second phase will be conducted later in the year.