The oil and gas industry, while crucial for global energy needs, has been marred by several catastrophic incidents, including the Piper Alpha explosion, the Deepwater Horizon oil spill, and the Exxon Valdez oil spill. These incidents have resulted in extensive environmental damage, significant economic losses, and, most tragically, loss of life. The analysis of these major accidents reveals critical lessons in areas such as safety culture, risk management, and regulatory oversight. Key lessons learned emphasize the importance of rigorous safety protocols, comprehensive risk assessments, asset integrity management, process safety management and the implementation of advanced technologies for real-time monitoring and emergency response. The need for continuous training and development of personnel, along with fostering a safety-first culture, is paramount. Additionally, the role of stringent regulatory frameworks and the enforcement of compliance cannot be overstated. These incidents highlight the necessity of transparent communication and collaboration among stakeholders, including industries, regulatory bodies, and communities, to prevent future disasters. By integrating these lessons into operational practices and regulatory policies, the oil and gas industry can enhance safety, minimize environmental impacts, and ensure sustainable operations. This paper discusses in detail 5 most devastating incident in Oil & Gas Industry, their root causes & contributing factors and the key lessons learnt to avoid such incidents in future.