Purpose: Frequent renegotiations within public-private partnership (PPP) have been recognised and affect project efficiency. Literature has focussed on diverse issues associated with renegotiation within PPP, especially in Latin America and Europe. However, a systematic summary what they have already provided appears lacking. Thus, the paper aims to conduct a critical review of publications concerning PPP renegotiation and explore the status quo, future interests and gaps in research.Design/methodology/approach: This study carried out a four-phase literature review research framework to identify the quality PPP-renegotiation articles published from 2003 to 2020. Assessing the full articles for eligibility by providing a structured summary including: background; objectives; data sources; study appraisal; results; limitations; conclusions and implications of key findings. After that, filtering papers associated with PPP renegotiation in terms of the structured summary, and a total of 60 research papers were selected in the database of web of science and Scopus for review.Findings: Methods adopted by researchers, research topics and theoretical foundations of PPP renegotiation research in different disciplines were identified through content analysis. Amongst the popular research topics identified were renegotiation factors, the outcomes with renegotiations, the framework to deal with renegotiations and contract design dealing with renegotiation based on rigid or flexible contracts.Originality/value: This study contributes to the current body of PPP knowledge by revealing the research trend in the past 20 years. It also points out the directions that the renegotiations of PPP research may go towards in the future. Moreover, this study is very valuable in understanding how governments and concessionaires effectively handle renegotiations.

This study introduces a colored network motif approach to systematically analyze micro-level collaboration patterns in PPP project networks from China's transportation sector. By distinguishing node types (e.g., contractors, investors) and tie strengths (e.g., strong vs. weak collaboration), the analysis uncovers statistically significant triadic motifs that reveal structural dominance and evolutionary features. Using a longitudinal, multi-project dataset (2014–2021) and degree-preserving randomized network benchmarks, the study ensures robust identification of overrepresented local structures. Key findings show that (1) in terms of heterogeneous-node local relationship patterns, construction contractors emerge as dominant players, with fully connected triads and structural hole triads wherein dyads are different types of organizations identified as motifs; (2) concerning heterogeneous-edge patterns, even though weak-tie subgraphs form the basic path of the networks, stable strong-tie subgraphs, representing collaboration alliances, become increasingly prevalent among organizations. This study contributes in three key ways. First, it advances project network analysis by shifting the analytical lens from macro-level structures to micro-relational patterns, enabling the identification of recurrent subgraph configurations among PPP actors. Second, it operationalizes colored motif detection to empirically capture both node- and edge-level heterogeneity in PPP networks. Third, it offers new theoretical and practical insights into the evolution of collaboration structures, showing how motifs such as structural holes reflect underlying governance logics.

Purpose: The nature of public-private partnership (PPP) markets, industry competition, and organizational embeddedness (e.g. collaboration experience), significantly influence how private-sector organizations in PPP establish relational ties and create project networks during the PPP procurement phase. This necessitates a multi-level perspective to unveil the relationship mechanisms and behaviors of organizations in PPP at different levels. This study aims to analyze the industry, clustering, and local characteristics of organization relationships using a longitudinal dataset of PPP transportation projects sourced from the National PPP Integrated Information Platform (NPPPIIP).Design/methodology/approach: This study adopts a multi-level analytical approach, encompassing whole-network, clustering-network, and local-network levels, to explore the mechanisms of organizational relationships and behavioral patterns within collaboration networks among private-sector organizations.Findings: The results indicate that (1) organizational relationships within PPP unfold spontaneously over time, driven intrinsically and collectively, devoid of prior planning, control, external direction, or imposed order at the industry level, with the evolution of four collaboration types elucidating the emergence of self-organizing networks; (2) super enterprises exhibit exceptional breadth, brokerage, and ego abilities, and relationship patterns are governed by the effects of geographic proximity and preferential attachment at the clustering level; and (3) local relationship patterns are characterized by embeddedness mechanisms, including relational and structural aspects.Originality/value: The multi-level analysis framework enhances our understanding of organization interactions in the PPP procurement phase, breaking away from the traditional social network analysis (SNA) at both the network-centric and ego-centric levels. Overall, the insights are valuable for policymakers designing improved tendering processes and for PPP private-sector organizations seeking a comprehensive overview of competition and collaboration in the transportation infrastructure sector.