Purpose: Public‐private partnerships (PPPs) are being faced by risk threats, notwithstanding the fact that the PPP model has been structured in a way that the associated risks are shared by both the public and private sectors. Consequently, the sources of risk change over the PPP project phases. Thus, the purpose of this paper is to identify and assess the risk factors in PPP infrastructure project phases comprising development phase, construction phase, operation phase and project life cycle through an empirical approach. Design/methodology/approach: The study adopted four different data-gathering approaches including literature review, desk review, brainstorming session and questionnaire survey. In order to capture a broad perception of stakeholders, the questionnaires were administered to three different stakeholder organizations to include public sector authorities (i.e. ministries, department and agencies), concessionaires and lenders/banks involved in different PPP infrastructure projects implementation in Nigeria. A total of 81 questionnaires were administered, out of which 63 were retrieved but after checking through the completed questionnaires, 60 questionnaires were found suitable for the analysis. Data collected were analyzed using descriptive statistics, mean score, Kruskal–Wallis test and the risk significance index in terms of severity and likelihood of occurrence conducted. Findings: In total, 70 risk factors were identified with respect to PPP project phases and their relative importance was gauged. In addition, the analysis of total 70 risk factors in the development phase, construction phase, operation phase and project life cycle phase indicated that 51 risk factors are located in the yellow zone, which is considered as moderate and 19 risk factors are located in the red zone that are regarded as critical. Practical implications: The identification of specific critical risk factors in each PPP project phase will provide a benchmark in developing risk management programs in developing countries. Originality/value: These study findings would be useful for PPP stakeholders to focus their attention, priorities and leadership in managing these critical risk factors. Furthermore, the findings of this study are significant in providing an in-depth understanding of the current Nigeria’s PPP market environment, which is a true reflection of developing countries as a whole.
