In health and education PPPs, the private consortium usually designs, builds, and operates the non-medical services in the institution, whereas in prison PPPs the company may also operate the actual prison services as well.

PPPs in public service sectors have been highly controversial: while investment has been sorely needed into new infrastructure, there's reason to believe that the PPP price tag has simply been too high, and that the expected service levels haven't been delivered.

There are a number of purported advantages of public-private partnerships over conventional procurement contracts. Most of them, however, do not withstand a close examination.

Value for money?

Most practitioners agree that value for money should be the driving factor in any decision to use a PPP. However experience shows that this is rarely the case. There is no standard definition of value for money, and the methods for assessing it are subjective and open to manipulation.

In theory, risks in PPPs are transferred to the party most able to limit and control them. In practice, however, whenever the private sector takes on risk, it expects a considerable profit for doing so.

Part of the potential efficiency of infrastructure projects consists of completing the construction on time and on budget. Claims that public-private partnerships offer particular advantages in this regard are mostly unfounded.

The main claim justifying PPPs in spite of their higher financing costs is the increased efficiency from the competitive tender and the private sector’s supposed operating efficiencies. However, in practice, due to their complexity only a few companies can afford to bid for PPPs and there has therefore often been a lack of competition, resulting in increased costs that may have wiped out the 'value for money' justifications for using PPPs in the first place.

Most practitioners agree that value for money should be the driving factor in any decision to use a PPP. However experience shows that this is rarely the case. There is no standard definition of value for money, and the methods for assessing it are subjective and open to manipulation.

Infrastructure schemes - whether PPPs or not - often suffer from governance problems including poor planning, low administrative capacity of public officials to oversee projects, and lack of transparency. PPPs can make these problems more difficult to uncover and resolve because of their complexity and lack of transparency.