& Research Paper On Relationships Between Material Flow and Economic Development in an Economic–material Flow System Yuan Tian 1,2 , Shoubo Xu 1,2 , Li Wang 3 and Peggy Chaudhry 4 * 1 School of Economics and Management, Beijing Jiaotong University, Beijing 100044, China 2 Center of China Technological Economics Research, Beijing Jiaotong University, Beijing 100044, China 3 School of Economics and Management, Beihang University, Beijing 100191, China 4 Villanova School of Business, Villanova University, Villanova, PA 19085, USA Based on material flow (MF) theory, this paper proposes two kinds of relationships between MF and economic development in an economic–MF system. First, the relation- ship between MF input and economic output, weighed by the two indexes ‘MF economic efficiency (MF economic effect coefficient)’ and ‘MF input coefficient (MF consumption coefficient)’; and second, the relationship between MF input increment rate and economic output increment rate, weighed by the index ‘MF input elasticity coefficient’. Using a mathematical interpretation among the above three indexes, the authors propose the developing and changing patterns of the three indexes with demonstration analysis. Copyright # 2009 John Wiley & Sons, Ltd. Keywords material flow; economic development; material flow economic efficiency; systems thinking INTRODUCTION Economic material flow (MF) is a most important tool in industrial ecology that affects the current economic society (Xu, 2005, 2006a). In this system, it is necessary to investigate the relation- ship between MF and economic development for research on MF in the economic field. Based on the theory of the six elements of production (Xu, 2006b) MF refers to transportation capacity, while according to the theory of levels of production (Xu and Xu, 2006), MF refers to MF enterprise (unit production element) and MF industry (industry production element). In the economic field, MF is generally regarded as an essential input of element of production—the ‘transpor- tation capacity’. This paper focuses on two kinds of practical relationships between MF and economic development, i.e., that between the MF input and the economic output, and that between the MF input increment rate and the economic output increment rate. Systems Research and Behavioral Science Syst. Res. 26, 259^267 (2009) Published online 6 March 2009 in Wiley InterScience (www.interscience.wiley.com) DOI :10.1002/sres.977 * Correspondence to: Peggy Chaudhry, Villanova School of Business, Villanova University, Villanova, PA 19085, USA. E-mail: peggy.chaudhry@villanova.edu Copyright # 2009 John Wiley & Sons, Ltd.