The science of soil mechanics has developed to such an extent in recent decades that its application in construction has almost become a matter of course, and a thorough examination of the subsoil is required just as it is for other building materials. This is likely why the testing methods of soil mechanics have been included for the first time in Volume III "Testing of Non-Metallic Building Materials" of the second edition of the Handbook of Materials Testing. The contribution "Testing of Foundation Soil and Soils" is structured in a way that, in line with the character of a handbook, allows the reader to conduct the field and laboratory tests that are now considered standard both domestically and abroad, without needing to refer to other specialized books.