The UK National Audit Office (NAO) scrutinises public spending on behalf of Parliament, helping it to hold government departments to account and helping public bodies improve performance and delivery. We publish around 60 value for money studies each year across a range of government activities, of which, around three of these usually cover transport topics. Our reports look at how government projects, programmes and initiatives have been implemented and make recommendations on how it can be improved. Our value for money work is not strictly ex-post assessment in the usual sense of assessing a programme once it has been in operation for some time. Due to the length of time needed to complete major transport investments and our remit to focus on accountability, we often carry out an assessment of a project before its completion. In some cases, particularly for significant infrastructure investments, a series of value for money reports is appropriate as the programme will develop over time. These tend to focus on how the programme is being delivered, in terms of the planning, procurement or construction phases of infrastructure projects.