Peering deeply into a huge patch of sky the size of three full Moons, NASA’s James Webb Space Telescope will undertake an ambitious program to study half a million galaxies. Called COSMOS-Webb, this survey is the largest project Webb will undertake during its first year. With more than 200 hours of observing time, it will build upon previous discoveries to make advances in three particular areas of study. These include revolutionizing our understanding of the Reionization Era; looking for early, fully evolved galaxies; and learning how dark matter evolved with galaxies’ stellar content. With its rapid public release of the data, this survey will be a primary legacy dataset from Webb for scientists worldwide studying galaxies beyond the Milky Way.