Tools for High Performance Computing 2009 : Proceedings of the 3rd International Workshop on Parallel Tools for High Performance Computing September 2009 ZIH Dresden As more and more hardware platforms support parallelism parallel programming is gaining momentum. Applications can only leverage the performance of multi core processors or graphics processing units if they are able to split a problem into smaller ones that can be solved in parallel. The challenges emerging from the development of parallel applications have led to the development of a great number of tools for debugging performance analysis and other tasks. The proceedings of the 3rd International Workshop on Parallel Tools for High Performance Computing provide a technical overview in order to help engineers developers and computer scientists decide which tools are best suited to enhancing their current development processes.