Contract, network or hierarchy? Selecting governance mechanisms in megaprojects from the perspective of contractor alliances
基于交易成本经济学，通过中国某大型基建项目的纵向案例研究，分析了承包商联盟在不同阶段选择合同、网络或层级治理机制的原因，发现机会主义行为可能性、不确定性和阶段时长共同决定选择，且三种机制在多个阶段互补。
Understanding the evolving governance mechanisms in megaprojects is crucial for reducing transaction costs and ensuring project success. However, previous literature primarily discusses the results of selecting governance mechanisms at different phases, with little research exploring the reasons behind these choices. To fill this gap, this article addresses the question of how to select effective governance mechanisms at different phases from the perspective of contractor alliances, based on transaction cost economics (TCE). We employ a longitudinal exploratory case study method to analyse the governance mechanism selection process across three phases (i.e. contractor alliance formation phase, shield construction phase and crisis response phase) of a large infrastructure project in China. The results indicate that the likelihood of opportunistic behaviour, uncertainty and the duration of the phase jointly explain the reasons for selecting specific governance mechanisms. Additionally, we also find that contractual governance, network governance and hierarchical governance are typically complementary in multiple phases of megaprojects. This article provides valuable managerial insights for future governance practices in megaprojects.