ALL of mine are sorted by drive (each have their own drawer) 1/4, 3/8, 1/2, then they are sorted by SAE/Metric, SAE on the left, Metric on the right. Wrenches, same way, each have their own drawer as to type of wrench, SAE on the left, Metric on the right. Everything that has SAE and Metric is sorted that way, nut drivers, allen wrenches, even my screwdrivers. :D