Wood’s complex structure makes it highly resistant to biological or chemical decomposition. The structure includes cellulose, long chains of linked sugar molecules, embedded in a scaffolding of a chemical known as lignin. Brown rot fungi, however, possess a unique ability to attack the cellulose fraction of wood while avoiding the surrounding lignin. This study provides evidence that brown rot fungi accomplish this using a two-step process. The steps are (1) secrete a set of chemicals and enzymes that open up the lignin framework and (2) release a second set of enzymes that break down the cellulose chains into sugars. The sugars are absorbed by the fungi and could be the basis for biofuels.