Guidance on the development of Business Cases - March 2016
3 STAG and the Business Case Development Process
Scottish Transport Appraisal Guidance (STAG) represents the first stage in the assessment of potential solutions to transport problems and can be seen as forming the key part of the Strategic Business Case.
The STAG process is designed to:
- identify existing and potential problems in the transport network;
- identify a range of schemes which could address these problems;
- assess these schemes against a range of criteria, including Value For Money (VFM).
As such, it is clear that the outcomes of a STAG report would be expected to contribute significantly to the strategic and economic elements of the business case, but less to the commercial, financial, and management elements.
The STAG process results in potential solutions to a transport problem and provides the information required for a decision maker to choose a preferred option or options.
This preferred option or options are then subjected to detailed design work and as a single preferred option is developed it is appropriate to revisit the STAG process in terms of this detailed design. This check should be to ensure that the original objectives are still being met but there should also be an update of the assessment against the STAG criteria. There is no requirement to revisit previous options unless the performance of the preferred option is significantly degraded.