Recommendation 14

The IPA and NIC stated that programmes should provide a reasonable range of outcomes for likely costs and schedule that reflects the level of uncertainty in a programme.23 The Comptroller and Auditor General has also recommended the use of 16 Q 82 17 Q 85 18 Q 3 19 Q 5 20 National Infrastructure Commission submission, page 2–3 21 Q 22 22 National Infrastructure Commission submission, page 2 23 Q 21; National Infrastructure Commission submission, page 2 Lessons from major projects and programmes 11 ranges.24 Ranges will necessarily be large at the early strategic outline business case stage, and as a programme goes forward, should narrow as more becomes known. The NIC said that its Rail Needs Assessment uses its latest best practice on using ranges for cost estimates. The IPA stated that as a programme goes towards the outline business case stage it expects that ranges will narrow down to plus or minus 25 to 30% and would like to see cost estimates with an accuracy of plus or minus 10% by the final business case stage.25 Skills and Leadership