Around the world, many companies are often employed by governments and other companies, to carry out jobs for specific purposes. Because of the nature of the jobs, in that they may impede on local laws and other regulations, a project agreement is needed.

The project agreement specifically governs the relationship, rights and obligations between the public authority and the company working on the project that is to be financed, throughout the entire term of the project. It can also be called a concession agreement.

In early PFI projects, it was common to have separate agreements for different phases of the project, such as a development agreement for the design and construction phase and an operating or facilities management agreement for the operating phase. However, it is now more common to have a single project agreement covering all aspects of the project.

In this way, the public authority grants a licence to the company working on the project. This would occur where no property interest could be granted or would be needed.