『Abstract
　Energy efficiency in industrial boiler steam systems can be very low due to old technologies, improper design and non-optimal operation of the steam systems. Solutions include efficiency assessments and investment\s in steam system optimizations, education and training for operators of the systems. This paper presents case studies on assessing and investing in boiler steam systems in China and Vietnam. Methodologies and approaches for data collection and analyses were designed specifically for each of the two countries. This paper concludes: (1) investing in energy efficiency in industrial boiler steam system in China and Vietnam are cost effective; (2) government should not sent national energy efficiency standards lower than that of energy companies or energy equipment manufactures.

Keywords: Energy system optimization; GHG mitigation; Global environment investment』

1. Introduction
2. Methodology, approaches and data
3. China
　3.1. Background
　3.2. GEF financing an industrial boiler project
　3.3. Achievement of objective and outputs
　3.4. Global environment benefits
4. Vietnam
　4.1. Background
　4.2. Description of an industrial boiler project
　4.3. Effectiveness and benefits of the project
5. Conclusions and implications
Acknowledgements
References