It depends on the development of relationships of trust built on successful partnerships with project developers, which are repeated where there is a steady pipeline of projects let as PPPs by the public sector (Sharma 2013). In addition they will be assessed for their risks, levels of return, volatility and whether there may be an element of natural monopoly (e.g. toll bridges or tunnels). This usually includes an undertaking from the government to refrain from investing in competing infrastructure or compensating the concession holder if it does make this kind of investment.