Abstract: Fluid-structure interaction (FSI) is ubiquitous in the natural and engineered world, and a better understanding of FSI systems can aid in the design of renewable energy harvesting technologies, bio-inspired propulsion vehicles, and biomedical devices (to name a few applications). In this talk we will investigate “inverted” flag flapping, in which the flag is clamped at its trailing edge with respect to the incoming uniform flow. This canonical system exhibits a diverse range of behavioral regimes, including flapping with amplitudes comparable to the flag length, making it promising for energy harvesting. We will identify the physical mechanisms responsible for the onset of flapping, the role of vortex shedding in flapping, and the chaotic flapping regime that the system undergoes for different parameters. We will also characterize the effect of nonuniform flexibility in the dynamics of this beautiful FSI system, and discuss some efforts for reduced-order modeling of these varied behaviors.