Author: R.F. Isbell, National Committee on Soil and Terrain The Second Edition of the Australian Soil Classification (Isbell and NCST 2016) is now available. It includes updates from the National Committee on Soil and Terrain (NCST), especially in regards to new knowledge about acid sulfate soils (sulfidic materials). Modifications include expanding the classification to incorporate different kinds of sulfidic materials, the introduction of subaqueous soils as well as new Vertosol subgroups, new Hydrosol family criteria and the consistent use of the term reticulate. All soil orders except for Ferrosols and Sodosols are affected by the changes.