int . j . prod. res., 2001, vol. 39, no. 8, 1559±1573 Green MRP: identifying the material and environmental impacts of production schedules S. A. MELNYKy*, R. P. SROUFEz , F. L. MONTABON§ and T. J. HINDS} Interest in environmentally responsible manufacturing has increased in recent times. However, this attention has focused primarily on the design activities of the ®rm. Largely overlooked have been the planning/scheduling activities of manufacturing. This paper introduces a new tool that integrates environmental concerns into the material planning activities and identi®es the waste streams generated in both quantitative and ®nancial terms. This approach should be interesting to practitioners and researchers in that it is based on the widely used MRP processing logic. This new approach is called Green MRP. Examining the feasibility and eŒectiveness of this procedure, the research pre- sented draws on production data for a taillight assembly produced by an American automobile manufacturer. The results show this approach is not only feasible but also has great potential 1. Introduction Environmental issues are becoming increasingly important to manufacturing managers, their employees, investors and researchers. Contributing to this import- ance are governmental regulations, international certi®cation standards (most notably ISO 14000) (Daniels 2000), and changing consumer demands. Playing a major role as well is the acceptance of developments such as Just-in-Time and Total Quality Management. Because these developments focus on the identi®cation and elimination of waste, they force managers to deal with pollution as a form of waste (Porter and van der Linde 1995a, b). Consequently, managers are being pressured from all sides to produce more quickly better and less expensive goods in such a way as to generate less waste during production, storage, usage and disposal. Paradoxically, however, manufacturing managers are not responding to this challenge by adopting environmentally responsible manufacturing systems. Even in the face of a growing number of positive and negative sanctions, most resort to end-of-pipe solutions (those that deal with pollution after it has been created) instead of implementing proactive solutions to pollution (those that focus on underlying International Journal of Production Research ISSN 0020±7543 print/ISSN 1366±588X online # 2001 Taylor & Francis Ltd http://www.tandf.co.uk/journals DOI: 10.1080/00207540010022980 Revision received May 2000. { Department of Marketing and Supply Chain Management, The Eli Broad Graduate School of Management, Michigan State University, East Lansing, MI 48824-1122, USA. { Boston College, The Wallace E. Carrol School of Management, Operations and Strategic Management Department, Fulton Hall, 140 Commonwealth Avenue, Chestnut Hill, MA 02467-0433, USA. } Iowa State University, College of Business, Department of Logistics, Operations and Management Information Systems, 300 Carver Hall, Ames, IA 50011-2063, USA. } Case Center for Computer-Aided Engineering and Manufacturing, College of Engineering, Michigan State University, East Lansing, MI 48824-1126, USA. * To whom correspondence should be addressed.