Book excerpt: The world of logistics has considerably changed due to globalization, modern information technology, and especially increasing ecological awareness. Large Supply Chain Management (SCM) systems are developing to global logistic networks. This book reflects major trends of the recent decade in SCM and, additionally, presents ideas and visions for logistic networks of the 21st century. Among the various aspects of SCM, emphasis is placed on reverse logistics: closing the loop of a supply chain by integrating waste materials into logistic management decisions.