A rapidly growing literature examines the downsides and benefits of smart transport infrastructure development. In particular, significant problems arising within urban conurbations can be addressed given the potential of advanced technology such as Big Data, the Internet of Things (IoT), and Artificial Intelligence (AI). Challenging issues, including pollution, rapid population growth, and traffic jams, may be lessened through these tools and technologies. However, smart transportation projects require expertise and very high levels of funding, and these issues can lead to risks during the implementation phase and the operation stages. Recent literature has canvassed the possibility of using hybrid Public Private Partnership (PPP) models to raise and allocate finance; however, there remain ‘unknown’ aspects of smart transport infrastructure projects that are not completely addressed, even with careful consideration and detailed evaluation. Thus, this chapter aims to investigate the cost-benefit outcome and determine the major categories of cost-benefit to be considered by PPP investors when investing in ‘smart’ transportation infrastructure. The study used a mini-scoping review focused on smart transportation infrastructure projects financed by PPP arrangements to create major cost-benefit category factors. This paper addresses a somewhat unexplored area regarding the cost-benefit of data-sharing and integrated technology and the risks leading to cost overruns when investing in PPP smart transportation infrastructure.