1.21 PFI arrangements are meant to lead to better design and performance by transferring the risk to the most appropriate party. The Trusts are meant to be able to require the PFI companies to build the hospitals to the required specification. The PFI companies and investors are meant to rely on their contractors to manage the design of the projects. The investors' payments to the PFI companies are made in line with technical adviser reports that track progress against plan and provide no assurance over the design. We have not looked at what went wrong with the design process within Carillion and its subcontractors. NHS England & NHS Improvement (NHSE&I) and some individuals involved in the projects told us that one of the causes may have been that Carillion's original pricing for the two construction contracts was too low to meet the required specification.