Journal Orbit Analysis is a useful computer tool for bearing system design and troubleshooting. This paper is a handbook for interpretation of calculated journal orbit data and plots. The Interpretive techniques presented here apply to any of the Journal Orbit computer programs available.Journal Orbit summary data and plotted output are both discussed in detail. Limits are recommended for summary parameters, and charts are provided to show how typical bearings conform to those limits. Interpretive examples of typical computer plots are also included in the text.