The practice of implementing infrastructure projects through a public-private partnership (PPP) arrangement is widely employed around the world with successful outcomes. However, this practice is not without challenges related to cost, time and quality variations, which the public is forced to bear. This study aims to explore factors influencing the termination of the East West Link project in Melbourne and present time and cost variation challenges facing the Sydney Light Rail project. This paper utilizes literature, investigating the critical success factors (CSF) for PPP infrastructure projects in an international context, and other readily available data sources such as Australian government publications, the case projects’ reports, news articles, and websites as the sources of data. The data gathered from these sources was then analysed to understand the project challenges and to investigate the relationship between CSF and the challenges. Four challenges were identified, including insufficiency of the business case, political interference, non-independence of implementing organizations and insufficient risk profile identification. The findings can assist to cover the loopholes that might cause similar failures in project planning, risk management, and policy and guideline frameworks. However, efforts should be made in improving the existing policies to accommodate political interests as part of risk measures under the national PPP guidelines.

中文翻译：

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调查澳大利亚公私合作项目面临的挑战

通过公私伙伴关系（PPP）实施基础设施项目的实践在世界范围内得到广泛采用，并取得了成功。但是，这种做法并非没有与成本，时间和质量变化有关的挑战，而公众不得不承担这些挑战。这项研究旨在探讨影响墨尔本东西线项目终止的因素，并提出悉尼轻轨项目面临的时间和成本变化挑战。本文利用文献资料，研究了国际背景下PPP基础设施项目的关键成功因素（CSF），以及其他现成的数据源，例如澳大利亚政府出版物，案例项目的报告，新闻文章和网站，作为数据源。 。然后分析了从这些来源收集的数据，以了解项目挑战并调查CSF与挑战之间的关系。确定了四个挑战，包括业务案例不足，政治干预，实施组织的非独立性和风险状况识别不足。这些发现有助于弥补可能导致项目计划，风险管理以及政策和指南框架中类似失败的漏洞。但是，应根据国家PPP指南，努力改善现有政策，以适应政治利益，并将其作为风险措施的一部分。政治干预，执行组织的非独立性以及对风险概况的识别不足。这些发现有助于弥补可能导致项目计划，风险管理以及政策和指南框架中类似失败的漏洞。但是，应根据国家PPP指南，努力改善现有政策，以适应政治利益，并将其作为风险措施的一部分。政治干预，执行组织的非独立性以及对风险概况的识别不足。这些发现有助于弥补可能导致项目计划，风险管理以及政策和指南框架中类似失败的漏洞。但是，应根据国家PPP指南，努力改善现有政策，以适应政治利益，并将其作为风险措施的一部分。