The article discusses how YST Company improved their project construction cost management system to increase profitability and reduce overall costs. They used a combination of research methods like literature review, interviews, and practical application to identify management deficiencies and irregularities in project operations. By analyzing project cost management content and consulting with construction project managers, they suggested optimizing the cost management system. The key findings include establishing the project manager as the center of cost control, creating a cost management organization system, and implementing cost management measures online.