Jeffrey Hittinger - Lawrence Livermore National Laboratory, Center for Applied Scientific Computing Scientists and engineers use numerical simulation to answer questions reliably, accurately, and, most importantly, quickly. In the history of HPC, hardware improvements have allowed for the solution of larger and more difficult problems. However, better hardware is only part of the solution. Advances in scalable algorithms have also enabled large-scale simulation. We will discuss some of the common scalable algorithm motifs used in scientific simulation including recent advances that exploit the growing concurrency of modern HPC platforms.