A researchers group of Hajime Tanaka simulated glass formation in supercooled liquids. To probe whether atomic slowing depends on local ordered structures, they measured a parameter based on atom packing. This indicated a statistical structure-dynamics correlation, confirming vitrification is thermodynamically driven. The length-scales of this correlation are linked to the α and β modes of glassy dynamics. This may resolve a long-standing dispute, possibly enabling a universal theory of glasses.