Corruption in infrastructure development, particularly in national strategic projects (PSN), remains a significant challenge in Indonesia, with a notable increase in cases within the transportation sector. Indonesian Corruption Watch (ICW) reported a 50% increase in corruption cases between 2015 and 2018, with billions of rupiah lost due to fraudulent practices in infrastructure projects. The paper emphasises the need for more proactive measures, particularly preventive actions, to tackle corruption effectively in PSN projects. While judicial efforts to address corruption, such as the establishment of the Tim Pengawal dan Pengaman Pemerintahan dan Pembangunan (TP4), have yielded some results, they were later revoked due to inefficiencies. This research advocates for a comprehensive approach, integrating both preventive and punitive measures, led by the Attorney General’s Office (AGO), to safeguard public resources and maintain the integrity of strategic national projects. Through a doctrinal research method, the study critically evaluates the role of the AGO, proposing a more robust and inclusive strategy that balances legal enforcement and preventive initiatives. Additionally, the paper explores the concept of ultimum remedium, emphasising that penal sanctions should be the last resort after all preventive avenues have been exhausted. Ultimately, the research underscores the need for a systemic overhaul, strengthening institutional frameworks and promoting transparent governance to mitigate the social cost of corruption and support the sustainable development of Indonesia’s infrastructure.