In this lecture, Prof. Southard continues his exploration of sediment transport by focusing on how sediments move, how transport is measured, and how different flow conditions create distinct bedforms. He explains key concepts such as bedload and suspended load, transport rates, and the challenges of measuring sediment movement in natural systems. The lecture also introduces aeolian (wind-driven) transport, highlighting saltation and the role of density differences between air and water. A major portion is devoted to the formation and evolution of bed configurations—especially ripples and dunes—using both laboratory flume experiments and natural examples to illustrate how flow velocity, sediment size, and turbulence interact to shape the landscape. Southard emphasizes the dynamic feedback between flow and sediment, showing how bedforms both result from and influence fluid motion.