This is a revised and updated edition of the highly successful first edition. In the intervening period the procedures used in the description of soils and rocks have continued to develop and evolve and this new edition incorporates changes in the national and international standards, BS 5930:2015 and EN ISO 14688 and 14689 and makes close comparison with US practice in description (ASTM D2488) and classification (ASTM D2487). In addition, changes in definitions, naming procedures, and new terms are all included and explained.