Thesis (M.Eng.)--Massachusetts Institute of Technology, Engineering Systems Division, 2000.Includes bibliographical references (leaves 60-66).commerce will have to prove its reliability and convenience. Operational excellence and coordination among the supply chain will allow e-vendors to offer services like on-time delivery and simple return processes, vital factors for electronic vendors' success. The purpose of this thesis is to identify the differences across the reverse logistics process. To accomplish this, the return policies and procedures of ninety-three leading companies that sell products on the Internet directly to consumers were carefully studied. Seven different return processes and four main activities included in them were identified and formally described. Each process is designed to satisfy a specific set of needs, thus they differ considerably from each other. Since logistics is a major part of the cost structure of operating a virtual store (e-tailer) every aspect of it has to be carefully studied and efficiently performed. The author has selected this sole aspect of reverse logistics to focus the research of this thesis and identify and describe the different processes that are currently used by e-vendors.by Hector Lozano Pruneda.M.Eng