The discussion of the complicating characteristics shows that re-manufacturing firms must be able to manage complex tasks that are significantly different from tasks in a traditional manufacturing environment. We find that the complicating characteristics must be considered as a whole, rather than considering the effects of each characteristic separately. Fig.2 shows the inter-relations among key decision points, and process and information flows for a re-manufacturing production planning and control system. In the following sub-sections, we discuss major research issues for each of the complicating characteristics (see Table 3). This section is based on information from the survey reported here, as well as the survey by Nasr et al. (1998), a thorough review of the existing literature (including working papers and workshop presentations), and follow-up telephone interviews with industry experts. In-depth case studies, highlighting the effects of particular characteristics would provide insights into how firms manage these complexities.