A public–private partnership (PPP, 3P, or P3) is a long-term arrangement between a government and private sector institutions. Typically, it involves private capital financing government projects and services up-front, and then drawing revenues from taxpayers and/or users for profit over the course of the PPP contract. Public–private partnerships have been implemented in multiple countries and are primarily used for infrastructure projects. Although they are not compulsory, PPPs have been employed for building, equipping, operating and maintaining schools, hospitals, transport systems, and water and sewerage systems.
Cooperation between private actors, corporations and governments has existed since the inception of sovereign states, notably for the purpose of tax collection and colonization. Contemporary "public–private partnerships" came into being around the end of the 20th century. They were aimed at increasing the private sector's involvement in public administration. They were seen by governments around the world as a method of financing new or refurbished public sector assets outside their balance sheet. While PPP financing comes from the private sector, these projects are always paid for either through taxes or by users of the service, or a mix of both. PPPs are structurally more expensive than publicly financed projects because of the private sector's higher cost of borrowing, resulting in users or taxpayers footing the bill for disproportionately high interest costs. PPPs also have high transaction costs.