Accurate forecasts of the likelihood and magnitude of a volcanic eruption in a specified timeframe are rooted in a scientific understanding of the processes that govern the storage, ascent, and eruption of magma. Yet our understanding of volcanic systems is incomplete and biased by the limited number of volcanoes and eruption styles observed with advanced instrumentation. This report identifies key science questions, research and observation priorities, and approaches for building a volcano science community capable of tackling them, and presents goals for making major advances in volcano science.