This Standard sets out a method for determining the shear strength of a soil (in terms of effective stress) by direct shearing in a shear box. Separate test procedures are described for the testing of low permeability soils such as clays or sandy clays (‘cohesive soils’) and highly permeable soils such as sands. For cohesive soils, different procedures are described for carrying out drained (or slow) shearing tests for determining the peak shear strength and for determining the residual shear strength.