UN Office for Internal Oversight Services (OIOS): OIOS is the internal oversight body of the UN Secretariat. It conducts program audits, evaluations, and investigations and is considered the internal watchdog of the UN. OIOS releases two annual reports that summarize its activities for the year in all three areas of its work (audits, evaluations, investigations). The report entitled Part I summarizes general activities and Part II summarizes peacekeeping activities.
In June 2013, OIOS started publishing its internal audit reports following a decision by the General Assembly, which can be found here: Internal Audit Reports
OIOS annual reports can be found here: Annual Reports