Public-private partnership as a driver of sustainable development: toward a conceptual framework of sustainability-oriented PPP

As an innovative model for infrastructure and public service delivery, public-private partnership (PPP) has become increasingly more popular around the world. PPP is facing the dilemma of development direction and value orientation since current studies and practices are mostly performed from an economic perspective. PPP leads according to sustainable development goals. This study briefly reviews the development of China's PPP and summarizes the characteristics of PPP in China through the theory of evolutionary economic geography. Secondly, a conceptual framework of sustainability-oriented PPP is proposed with three phases named PPP1.0, PPP2.0, and PPP3.0. Thirdly, a case study named the Taizhou commuter-rail Line S1 PPP project has been adopted to verify the theoretical framework of the sustainability-oriented PPP. Lastly, the theoretical framework is analyzed and discussed based on the four dimensions: driving force, subject, process, and object. The results show that the sustainability-oriented PPP framework explains the development process and trend of PPP, not only meeting the PPP development needs in China, but also providing a reference value for other developing countries. This study has implications for decision making in China's PPP policy and makes an innovative contribution to the global PPP knowledge body.