A pathology working group (PWG) consists of a panel of experts who are convened to address a specific question from a toxicity study or to resolve an impasse between the study pathologist and the peer reviewer. This presentation will cover: 1) the process of deciding when to conduct a PWG; 2) how a PWG is assembled; 3) the process of conducting a PWG; 4) possible outcomes of a PWG; and 5) the important items in a PWG report. Specific examples of actual PWGs and the problems solved will be shared.