The National Audit Office (NAO) is an independent organization in the United Kingdom responsible for auditing government departments and public sector organizations. Its primary role is to ensure that public funds are used efficiently and effectively, providing transparency and accountability in government spending. The NAO conducts various audits and reports on the financial health and performance of public services. By examining how taxpayer money is spent, the NAO helps improve public services and informs Parliament and the public about the government's financial management.