This thesis presents a Dalitz plot analysis of D0 to K0S PI0 PI0 using the CLEO-c data set of 818 inverse picobarns of positron-electron collisions accumulated at center-of-mass energy 3.77 GeV. This corresponds to about 3 million D0-anti-D0 pairs from which we select 1260 tagged candidates with a background of roughly 6%. We find that S-wave features dominate the PI0 PI0 axis of the Dalitz plot, contributing about one-third of the total decay rate, while the K*(892) is the dominant K0S PI0 contribution. Using three tag modes and correcting for quantum correlations we determine that the D0 to K0S PI0 PI0 branching ratio is 1.059% with a statistical uncertainty of 0.049% and a systematic uncertainty of 0.050%.