cost challenges and trade-offs associated with these application classes. The report addresses not only present-day applications and technology, but also the context provided by history, by institutions and communities, and by international involvement in supercomputing. Chapter 2 defines supercomputing. Chapter 3 outlines a brief history of supercomputing. Chapter 4 describes many compelling applications that place extreme computational demands on supercomputing. Chapter 5 discusses the design of algorithms, computing platforms, and software environments that govern the performance of supercomputing applications. The institutions, computing platforms, system software, and the people who solve supercomputing applications can be thought of collectively as an ecosystem. Chapter 6 outlines an approach to supercomputing ecosystem creation and maintenance. Chapter 7 discusses the international dimension of supercomputing. Chapter 8 offers a framework for policy analysis. Chapter 9 describes the role of the government in ensuring that supercomputing appropriate to our needs is available both now and in the future. Chapter 10 contains the committee’s conclusions and recommendations for action to advance high-end computing.