Part II of this report examines the issues considered from the point of view of the individual working groups. The reports of each of the working groups, as written by the participants, are provided the following four chapters. These chapters present the original findings of each group and are included so that readers may draw their own conclusions from the raw data. Because the authorship of these four chapters differ, style and form vary somewhat. But the underlying themes are the same: to characterize the state of the art, to identify principal barriers hindering progress toward PetaFLOPS, to reveal the best approaches toward this goal, and to propose near-term actions that would further these objectives. This chapter presents a brief overview of the following four chapters and their findings. It is offered to facilitate gaining a global perspective of the many complex and interrelated issues prior to examining the individual reports in more depth. In so doing, it provides a guide to the remaining chapters of this part of the report.