Abstract: A technique for interactively analyzing system log-files. System log-files, which are monitored by technical personnel and systems specialists to determine system performance, status, and software faults, are often generated during various hardware and software monitoring operations. Each log-file contains time stamped reports. This technique is especially useful for analyzing large log-files. A new release of software may contain many incremental versions that must be tested. The testing of each incremental version may generate a log-file containing thousands of reports. Using this technique, reports are correlated, faults are isolated, and temporal patterns are recognized more quickly and efficiently than by using conventional, non-graphical techniques.