COSINE-100 is a direct detection dark matter experiment that is testing DAMA/LIBRA's claim of dark matter discovery. Located in South Korea's Yangyang Underground Laboratory, COSINE-100 comprises 106 kg of sodium iodide detectors surrounded by a ~2000 L liquid scintillator veto. In this talk, I will present new results from an annual modulation search using three years of data and the impact on DAMA/LIBRA's discovery claim. I will also discuss improvements over our previous modulation analysis, including lowering the analysis threshold to 1 keV and the development of a more robust time-dependent background model. In addition, I will review ongoing R&D projects for, and the physics reach of future phases of the experiment.