This workshop was intended to bring the applications and tools communities who will be using petascale systems together so that they could influence each other to improve the overall state of petascale computing. Issues that came up during the workshop included the desire for: better tools, adjusted policies and practices in the centers, more libraries, better languages and programming models, more communication and better collaboration, and increased training and education. The next steps from the workshop are primarily educational, organizational, and communicational. The workshop was held on June 9, 2008.