Parliament revamp urged to "avoid HS2 and Crossrail cost trap"

Citing Crossrail and HS2 as examples from which to learn, the NAO says the decision of delivery bodies to publish ‘firm’ commitments too early brought external pressure to meet those commitments at the expense of value for money. Decisions on Crossrail were influenced and dominated by fixed completion dates and costs, the NAO says, due to the fact estimates were published without information on the level of uncertainty within them.