This case study provides an analysis of AGL Energy Limited's sustainable procurement journey through the lens of project integration. It begins by describing the Australian gas market, highlighting its regional divisions and structural changes. The study then examines future trends in the gas market, emphasizing cost reduction, digitalization, and talent development. AGL's sustainable procurement practices are outlined, focusing on their supplier code of conduct and risk management processes. The impact of new technologies, such as IoT and digital labor, on end customers and gas producers is explored, along with the effects of Australian LNG's strong position and regulatory uncertainties. Finally, the study proposes a project integration management plan with a focus on procurement, emphasizing clear accountabilities and integrated project teams. This analysis aims to provide insights into how AGL integrates sustainability into its procurement processes within the evolving energy landscape.