The DUNE (Deep Underground Neutrino Experiment) is a next-generation neutrino experiment designed to make precision oscillation measurements in a 1.2-2.4 MW neutrino beam, which is directed from Fermilab to the Sandford Underground Research Facility in South Dakota. The PRISM (Precision Reaction Independent Spectrum Measurement) concept presents a novel way to perform a neutrino oscillation analysis, which has the potential to significantly reduce the impact of neutrino cross-section systematic uncertainties in DUNE. The PRISM method linearly combines measurements of off-axis neutrino interactions at the DUNE near detector to produce data-driven predictions of the oscillated neutrino event rate spectrum at the far detector. By building an oscillated far detector prediction directly from data, any unknown or poorly modelled neutrino cross-section effects will be naturally incorporated into the measurement of the parameters of the neutrino oscillation model. This poster will give an overview of PRISM and how it is used in DUNE.