The evolution of Earth’s topography is commonly thought of as a balance between tectonic processes that produce topographic relief, and climate (through the process of erosion) that sculpts topography. The effects of near surface transient hydrologic and biologic processes on landscape evolution are, unfortunately, commonly ignored. In the last two decades, increasing interest has emerged to quantify the evolution of topography with physically based landscape evolution models. Recent cross-disciplinary enthusiasm to develop improved landscape evolution models is motivated by several factors, including: the need to predict changes in erosion and sedimentation rates in response to global warming scenarios; increased concern over soil loss; and to test the hypothesis that climate and tectonic processes are coupled through erosion and sedimentation.