Our premise is that TAU can provide a robust and widely applicable performance technology framework for complex parallel and distributed systems. This section presents brief selected performance scenarios that demonstrate that TAU can offer effective technology across complex systems types. We begin with an MPI example showing how communication events are instrumented and performance measured and visualized with respect to other application events. We then discuss multi-threaded applications and the techniques we have developed for Java. The main point to highlight is TAU's ability to support different high-level performance problem solving requirements via system specific instrumentation, measurement, and analysis.