PPP, also known as 3P mode, namely public-private partnership mode, is a financing mode for public infrastructure projects. In the process of cooperation between the public sector and the private sector, the non-public sector is allowed to participate in the provision of public goods and services, thus realizing the functions of the public sector and bringing benefits to the private sector. Its management mode includes many concrete forms consistent with this. Through this process of cooperation and management, we can provide public goods and services to the society more effectively, and make limited resources play a greater role, while not excluding and properly meeting the investment and profit objectives of the private sector.

The popular explanation is that the government contributes, and enterprises or financial institutions contribute to jointly build expressways. After the repair, they will get dividends by collecting tolls.